7345 SW 29th Avenue Portland, OR 97219
p 503.334.8634
f 503.892.2321
greengirl@greengirlpdx.com
www.greengirlpdx.com
STORMWATER MONITORING &
MAINTENANCE PLAN
TEMPLATE
City of Bend
LID Stormwater Demonstration Project
Bear Creek Road & Franklin Street
July 29, 2012
Final Plan Submittal
Prepared for:
Hickman, Williams & Associates, Inc.
62930 O. B. Riley Road, Suite 100
Bend, OR 97701
Project Manager: Rob von Rohr
Prepared by:
Green Girl Land Development Solutions
7345 SW 29th Avenue
Portland, OR 97219
Project Manager: Maria Cahill
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Table of Contents
Table of Contents .......................................................................................................................................................2
Abbreviations ..............................................................................................................................................................3
Introduction .................................................................................................................................................................4
Definitions ...................................................................................................................................................................4
Bear Creek Road Bioinfiltration Basins ......................................................................................................................5
Franklin Street Infiltration Planters .............................................................................................................................6
Significant Monitoring Questions ................................................................................................................................7
Understanding The Stormwater Management System ............................................................................................7
Maintenance ............................................................................................................................................................ 10
Schedule .................................................................................................................................................................. 10
Procedures .............................................................................................................................................................. 11
Equipment ................................................................................................................................................................ 11
Seasonal Considerations ......................................................................................................................................... 11
Monitoring Questions ............................................................................................................................................... 12
Monitoring Question 1: How effective is the facility at managing water from different size storm events? ............. 13
Overview .............................................................................................................................................................. 13
Hypothesis ........................................................................................................................................................... 13
Basis for Hypothesis ............................................................................................................................................ 14
Monitoring Element .............................................................................................................................................. 14
Monitoring Method ............................................................................................................................................... 14
Equipment Needed .............................................................................................................................................. 14
Data Collection Procedure ................................................................................................................................... 15
Data Collection Frequency & Duration ................................................................................................................ 16
Data Interpretation & Adaptive Management ...................................................................................................... 16
Additional Considerations .................................................................................................................................... 17
General Cost Considerations of Monitoring & Maintenance ............................................................................... 17
Monitoring Question 2: How does permeability vary with time & season? .............................................................. 18
Overview .............................................................................................................................................................. 18
Hypothesis ........................................................................................................................................................... 18
Basis for Hypothesis ............................................................................................................................................ 18
Monitoring Element .............................................................................................................................................. 19
Monitoring Method, Alternative 1: Infiltration Testing by Facility Flooding .......................................................... 19
Alternative 1: Equipment Needed ........................................................................................................................ 19
Alternative 1: Data Collection Procedure............................................................................................................. 19
Monitoring Method, Alternative 2: Double-ring Infiltration Testing ...................................................................... 19
Alternative 2: Equipment Needed ........................................................................................................................ 19
Alternative 2: Data Collection Procedure............................................................................................................. 20
Presoaking ........................................................................................................................................................... 20
Restore vegetation .............................................................................................................................................. 21
Data Collection Frequency & Duration ................................................................................................................ 21
Data Interpretation & Adaptive Management ...................................................................................................... 21
Additional Considerations .................................................................................................................................... 21
General Cost Considerations of Monitoring & Maintenance ............................................................................... 21
Monitoring Question 3: How do bioinfiltration facility maintenance practices affect plant health? .......................... 24
Overview .............................................................................................................................................................. 24
Hypothesis ........................................................................................................................................................... 24
Basis for Hypothesis ............................................................................................................................................ 24
Monitoring Element .............................................................................................................................................. 24
Monitoring Method ............................................................................................................................................... 24
Equipment Needed .............................................................................................................................................. 24
Data Collection Procedure ................................................................................................................................... 25
Preparing the Site ................................................................................................................................................ 25
Preparing to Take Photos .................................................................................................................................... 25
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Taking Photos ...................................................................................................................................................... 25
Data Collection Frequency & Duration ................................................................................................................ 26
Data Interpretation & Adaptive Management ...................................................................................................... 27
Additional Considerations .................................................................................................................................... 28
Additional Resources: .......................................................................................................................................... 29
General Cost Considerations of Monitoring & Maintenance ............................................................................... 30
Monitoring Question 4: Is non-irrigated vegetation successful? .............................................................................. 30
Overview (Bear Creek only) ................................................................................................................................ 30
Hypothesis ........................................................................................................................................................... 30
Basis for Hypothesis ............................................................................................................................................ 30
Monitoring Element .............................................................................................................................................. 30
Monitoring Method ............................................................................................................................................... 30
Equipment Needed .............................................................................................................................................. 30
Data Collection Procedure ................................................................................................................................... 31
Establish a Baseline in the Observation Area ..................................................................................................... 31
Perform Annual Site Visit in the Observation Area .............................................................................................. 31
Data Collection Frequency & Duration ................................................................................................................ 32
Data Interpretation & Adaptive Management ...................................................................................................... 32
40% Minimum Coverage is Maintained for 10 Years .......................................................................................... 32
Coverage Falls Below 40% ................................................................................................................................. 32
Additional Considerations .................................................................................................................................... 33
General Cost Considerations of Monitoring & Maintenance ............................................................................... 33
Monitoring Question 5: What is the maintenance cost and time needed? .............................................................. 34
Overview .............................................................................................................................................................. 34
Hypotheses .......................................................................................................................................................... 34
Basis for Hypotheses ........................................................................................................................................... 34
Monitoring Element .............................................................................................................................................. 34
Monitoring Method ............................................................................................................................................... 34
Equipment Needed .............................................................................................................................................. 34
Data Collection Procedure ................................................................................................................................... 34
Data Collection Frequency & Duration ................................................................................................................ 35
Data Interpretation & Adaptive Management ...................................................................................................... 35
Additional Considerations .................................................................................................................................... 36
General Cost Considerations of Monitoring & Maintenance ............................................................................... 36
Appendix A – Monitoring Data Recording Forms .................................................................................................... 37
Appendix B -- Worksheets for Data Analysis .......................................................................................................... 48
Appendix C -- Maintenance Requirements from the Central Oregon Stormwater Manual ..................................... 53
Appendix D -- Monitoring Question 1 Monitoring Device ........................................................................................ 61
Appendix E – Bibliography ...................................................................................................................................... 63
Abbreviations
COSM: Central Oregon Stormwater Manual
DEQ: Oregon Department of Environmental Quality
EPA: Environmental Protection Agency
HOA: Home Owner's Association
MQ: Monitoring Question
NOAA: National Oceanic and Atmospheric Administration
NPDES: National Pollutant Discharge Elimination System
UIC: Underground Injection Control
TEMPLATE INTRODUCTION
Some portions of this plan must be completed after construction or will require city staff input after our
contract is complete. Notes about this information will be formatted like this text in blue italics whose
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style is called GG Template. Specific information that may need to change or be completed will be
shown in [square brackets]. Once all the monitoring and maintenance plan has been completed by city
staff, it is recommended that staff delete all this additional information text at once.
Introduction
This monitoring plan is intended to give the City of Bend a few meaningful metrics by which to measure
the stormwater disposal effectiveness and “maintainability” of the various low impact development
facilities to be constructed at two different sites, Franklin Street and Bear Creek Road. This is not
intended to be a robust water quality monitoring plan, but some relevant information and planning in the
design has been included that will help in future monitoring efforts.
Figure 1 Map of Bend showing locations of Franklin & Bear Creek facilities
This report will define:





Significant monitoring questions
Guidance for proper maintenance procedures and frequency
Metrics for evaluating performance
When a conclusion may be drawn from the data, and
How and which adaptive management techniques should be applied upon reaching a
conclusion.
Definitions
Baseline: point of reference for measurements. May be the first measurement taken or a value that
serves as the ideal or goal of the design.
Bioinfiltration: The use of plants and soil to reduce stormwater runoff volumes primarily through the
mechanism of infiltration. The water balance of these systems will also include evaporation and runoff.
The Central Oregon Stormwater Manual (COSM) calls these facilities Bioinfiltration, while HWA and
others on the team call them Bioretention. These two terms can be used interchangeably, in this case.
Establishment Period: The amount of time a landscape xeriscaped with native and
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naturalized/adapted plants is estimated to need irrigation to develop enough roots to support plant
resilience through a wide range of natural and/or manmade conditions.
Heat Island Effect: According to the Environmental Protection Agency (EPA) website
(http://www.epa.gov/hiri/about/index.htm): “Buildings, roads, and other infrastructure replace open land
and vegetation. Surfaces that were once permeable and moist become impermeable and dry. These
changes cause urban regions to become warmer than their rural surroundings, forming an "island" of
higher temperatures in the landscape.” Heat islands may also occur on a much smaller scale; for
instance, comparing air temperatures in a landscape area next to pavement versus a landscape area in
the middle of a lawn or forest.
Major storm: Any storm with precipitation above 1 inch in a 24-hour period.
Photo point monitoring: The act of observing change over time by taking photos of specific and
significant areas of interest using well defined and repeatable camera and photo locations.
Pretreatment: The practice of reducing some pollutants
before they enter a stormwater facility. Most inlets at both
sites use catch basin inlets with sumps to settle out
particulates (i.e. dirt). This makes sediment removal easier
through traditional methods like a vactor truck and will
extend the life of the facility.
Figure 2 Regardless of the amount of
rainfall, Central Oregon's historic water
balance, on an average annual basis, is
comprised primarily of evaporation and
evapotranspiration
Water balance: Where, and in what form, water is in the
hydrologic cycle over an average annual year. The term
might be applied to a stormwater facility as well as a region.
Out of all the rainfall in Central Oregon, the average annual
water balance in natural, pre-developed areas is:
evaporation & evapotranspiration account for 68-96%;
runoff accounts for 1-23% (usually 4 to 8%); and infiltration
that recharges the groundwater is negligible (Roundy
1999). The pre-developed water balance is the "gold
standard" to which agencies might aspire to sustainably
restore their watersheds.
Underground Injection Control: “[A] device that places
fluids below the ground. Most UIC systems in Oregon are
shallow and widely used to dispose of stormwater, including
rainfall runoff and snowmelt, from properties, streets and parking lots owned and operated by public or
private entities. Businesses and industries may also use injection systems to dispose of water that has
come in contact with any raw material, product, by-product, or waste during manufacturing or
processing.” Definition from Oregon Department of Environmental Quality (DEQ) UIC website:
http://www.deq.state.or.us/wq/uic/uic.htm
Xeriscaping: “Commonly referred to as water-wise or water-smart gardening”. Definition from
Xersiscaping in the High Desert: http://extension.oregonstate.edu/deschutes/sites/default/files/xeriall.pdf.
Bear Creek Road Bioinfiltration Basins
The development of this project was driven by a Safe Routes to School grant that was meant to help
the City install sidewalks. Bear Creek is comprised of 3 separate bioinfiltration basins, Basins A, B, and
C, which will be used to identify the location of monitoring activities. They receive drainage from private
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and public roadways, sidewalks, and landscape areas, all of which may impact monitoring results.
Figure 3 Designations for the three different basins at Bear Creek
Franklin Street Infiltration Planters
The main driver for this retrofit project is to relieve localized flooding. Area for infiltration at this site is
limited by the narrow planter strip and the desire to preserve and protect the existing tree, so this site
uses stormwater planters with vertical side slopes to maximize runoff storage during floods. The
Franklin Street Infiltration Planters are comprised of two separate, but interconnected infiltration
facilities. Due to steep slopes, Stormwater Planter B has been designed as a series of cells (B1 through
B12) that cascade over partition walls, one to another. Stormwater Planter A is located in a more flat
area, so it was not divided into separate cells.
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Figure 4 Designations for the various facilities and cells at Franklin
Significant Monitoring Questions
These are the questions that have been identified as being significant at this time:
1.
2.
3.
4.
5.
How effective is the facility at managing water from different size storm events?
How does permeability vary with time and season?
How is bioinfiltration facility maintenance affecting plant health?
Is non-irrigated vegetation successful?
What is the maintenance cost and time needed?
Understanding The Stormwater Management System
These stormwater facilities were designed to use r esilient, easy -t o- see appr oaches wit h
redundancy to protect against flooding the City of Bend’s property and downstream neighbors in a
variety of rainfall events as well as providing the required level of water quality treatment
associated with new development in the City of Bend. Proper maintenance must be applied to ensure
that the system continues to work well over time.
During a storm, water falls on impervious surfaces (roads & sidewalks) and pervious surfaces
(landscape areas). At the beginning of the storm, the roughness of the surfaces absorb and store the
rainfall, but at some point on both the impervious and pervious surfaces, the capacity to absorb rainfall
is exceeded and runoff (admittedly at different times for different kinds of surfaces) begins. Water that
runs off in the drainage areas defined in the Drainage Reports generated by HWA makes its way to the
bioinfiltration areas. Depending on the facility and drainage area, some will enter via a pipe at the
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bottom of the facility and some will enter via a curb cut at the top. Much of the runoff will drain through
the surface to recharge the aquifer soon after entering the facility, but as the storm builds, the capacity
of the soil to pass water through will be reduced and water will begin to pond. In large, rare storms,
water will back out of the lowest elevation of the ponding area back into the public right-of-way. By the
time this happens, pollutants will have long been scoured and delivered to the bioinfiltration facilities so
that any remaining runoff bypassing the facility can be considered clean.
To properly maintain the systems, it is essential to know where to find each component, what function it
performs and to be aware of potential conditions that could decrease water quality and/or increase
maintenance if not addressed.On the re-developed property, you will find the following treatment and
conveyance facilities (letters in parentheses correlate to Figures 5 and 6).
Bioinfiltration basin (BB): These facilities clean runoff from all contribution areas, which are likely
to contribute dirt/particulates, feces, nitrogen, copper, zinc, mercury, other heavy metals, hydrocarbons,
pesticides, herbicides, insecticides and other pollutants from air or waterborne sources. Treatment of
some of these pollutants occurs in the basin through three processes:
 Settling: Large particles will settle out of the stormwater as it ponds. Many pollutants are
attached to trash and large and small soil particles.
 Physical filtration: Smaller particles and some heavy metals are filtered in the upper
reaches of the soil as water passes through it.
 Microbial remediation: Hydrocarbons from smog and oils are “eaten” (i.e. metabolized) by
microbes as the water passes through the soil.
 Plant uptake: Plants take up some pollutants and store them internally in their structure.
Three out of the four means of treatment above are a result of the water passing through the soil.
In addition, plants play a crucial role in these systems:





The structure of the plant helps slow the water to settle out more dirt.
The roots of the plants provide robust habitat for microbes, which attach and multiply
enthusiastically on the roots because the plant is pulling up the polluted water (microbe food)
through roots.
Larger soil animals, like worms and nematodes, which protect against clogging by naturally
aerating the soil, will be more numerous where there are plant roots than where there are not.
Plant roots reduce the effect of natural soil compaction, continually breaking up the soil and
allowing water to drain more freely through the soil than if no plant were present.
Plant roots hold soil which helps prevent it from polluting stormwater runoff. Unfortunately,
settling, soil, and plants don’t do a great job of removing soluble pollutants including nitrogen,
phosphorus, and heavy metals including zinc and copper. Prevention methods (aka source
control) to manage stormwater for these pollutants are included throughout this narrative and
in the maintenance matrices of Appendix C.
Catch Basin (CB): Standard catch basins in the City of Bend have a sump, an extra storage
depth beneath the lowest outlet pipe, to pond water and settle large sediments before runoff
leaves the catch basin.
Curb Cut (CC): This is a cut or hole in the curb that allows stormwater to enter the facility via
overland flow at the top of the facility. Depending on the grades and storm intensity, these may
serve as both inlets and outlets; however, all curb cuts for both projects have been designed to be
inlets only.
Day lit pipe (DP): Daylighting a pipe means that a pipe emerges from the ground to “see” the light
of day. Pipes daylight at the outfalls at the bottoms of each of the ponds at Bear Creek, and can be
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a source of erosion, but were a necessary design element that allowed stormwater from across the
street to be managed.
Energy Dissipater (ED): This consists of concrete pad and pile of rip rap (i.e. large angular rock) at
the various pipe and curb cut outfalls to protect against erosion.
Landscape areas (L): Landscape areas can be a significant source of pollution. Fertilizers,
pesticides, herbicides, fungicides applied during “routine maintenance”, and soil from bare spots can
easily run off and enter our streams. Landscape areas will be amended with compost to control runoff,
but many landscape areas contribute greater volumes of runoff than generally believed.
Partition Wall (PW): This is a structural wall used to pond water on steep slopes at Franklin, built
slightly lower than the walls along the curb and street to allow water to the next, lower cell without
overflowing into the street.
Roadways (RW): Roadways are the primary source of runoff to the facility, conveying runoff in all but
the smallest storms. They are the highest source of the pollution, with pollution increasing with average
daily trips.
Sidewalks (SW): Runoff from all the surrounding sidewalks on both sides of the street will
eventually make its way into the bioinfiltration basins.
Solid pipe (SP): The solid pipe conveys stormwater from the street catch basin inlet to the bottom of
the facility.
Wall (W): There are rock walls in Bear Creek and concrete walls at Franklin.
Figure 5 Components at Bear Creek requiring maintenance
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Figure 6 Components at Franklin requiring maintenance
Maintenance
Proper maintenance is crucial to facility functioning and to answering monitoring questions.
Maintenance schedules are more of an art than a science, so keep a close eye on your system for the
first two years to get a feel for when some activities might need to be done more often than these
minimum suggestions. For instance, areas with more foot traffic will receive more trash. Because a
number of monitoring questions will be answered during regular maintenance inspections, these
should be conducted with the facility drawings and this Stormwater Monitoring and Maintenance
Plan in hand to help the inspector understand how the facility is supposed to function. The Maintenance
Plan will help the inspector recognize signs that indicate diminished performance (for example, sediment
accumulation, vegetation die-off, or ponding water for more than 48 hours after a storm).
Schedule
Facilities should be inspected at least:



Quarterly for the first 2 years
Twice a year thereafter
Within 48 hours of major rainfall events (more than 1 inch of rain over a 24-hour period
which corresponds to the Water Quality, or First Flush, event.)
Additional periods on the Maintenance Form are:

monthly
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
once a year at a minimum
as needed, which may mean very frequent or very infrequent depending on the situation and
your own observations.
Procedures
Many maintenance procedures are prescribed by Appendix 12B of the Central Oregon Stormwater
Manual (COSM), which are included in Appendix C of this report. In cases where additional
maintenance may be required, we have added these procedures to the table.
Equipment








Puncture-proof Gloves
Reflective yellow safety vest
Vactor (suction, not pressure wash)
“Nifty Nabber” claw grabber
Trash bags
Safety Glasses
Ear Protection
Protective Boots
Seasonal Considerations
Some practices should be done on a regular basis. Others need only be done seasonally or annually
based on the activity. Seasonal considerations for maintaining different infrastructure components are
as follows:
Component or
Activity
Maintenance Best Performed in:
Spring
Remove Trash
& Debris
Control Animals
Summer
Fall
Additional Comments
Winter

Dispose of trash & debris appropriately.
Needles should be placed in a sharps container.
Do not place pest control or other poisons or
toxics in a box or out in the open within a
stormwater management facility. Contact animal
control.

Maintain
Equipment

Fix Erosion

Prevent spills. Place equipment on grassy area
that will not drain to a stormwater facility when
pouring in gas or performing other tasks that
could spill or leak fluids. Use a drip pan as
appropriate and dispose of fluids appropriately.
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Component or
Activity
Maintenance Best Performed in:
Spring
Summer
Fall
Additional Comments
Winter
   
Most sediment from roads is not considered
hazardous and can be disposed of in a landfill.
Toxic spills are possible; material collected after
spills should be disposed of according to the
COSM guidance for maintenance by HOAs.
Dewater
Sediment
   
If and when dewatering the soil is necessary,
dewatering back into facility or on a landscape
area is OK, but don't allow drainage to enter
stormwater system in the street.
Weeding
   
Remove
Accumulated
Sediment
   
Late winter or early spring. Pruning should be
performed carefully in the first few years to
reduce long-term maintenance and improve
overall health.
Pruning Grasses
   
Grasses don't require pruning. This is for
aesthetics only. Don't weed whack, which can
inhibit deep rooting and increase maintenance
from clogging, long-term. Instead comb dead
material by hand or with a rake.
Maintain
Irrigation
Systems
   
Water Plants
 
Pruning Trees &
Shrubs
Maintain
Structure (curb
cuts, catch
basins, energy
dissipaters,
curbs, walls)
   
As directed by specifications.
Before rainy season begins. Inspection of some
structures will require numerous visits during
the wet season. See Appendix C.
Monitoring Questions
Many of the following monitoring questions require knowledge of the most recent storm size. Data can
be gathered from the following sources: .
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
City of Bend Public Works at 575 NE 15th Street

Agrimet has an urban weather station in Bend and located in the Old Mill District at 301 SW
Shevlin Hixon Drive (data: http://www.usbr.gov/pn/agrimet/agrimetmap/bewoda.html).

The National Weather Service has data from a weather station at the Bend Municipal Airport
(data: http://www.weather.gov/obhistory/KETB.html) but weather patterns in Oregon are much
more localized than in other areas of the country, so this site may not be near enough to be
relevant in every storm event.

From research, it appears that an effective and high quality weather station can be purchased
from Oregon Scientific for about $200, which can be hard wired or run on batteries with the
option of uploading data automatically. Since rainfall can be so localized, these could be set up
at each monitoring site.
Monitoring Question 1: How effective is the facility at managing water from
different size storm events?
Overview (Bear Creek Only)
The City wishes to understand the overall performance of these facilities and their ability to reduce
runoff during a variety of real-world storms of different duration and intensities. Franklin and Bear Creek
are designed and modeled differently because of site constraints, so the runoff reduction capacity is
expected to be different at each site.
How effective a facility is at reducing runoff from a variety of storms in a variety of seasons is related,
among other factors, to the available storage volume and the infiltration rate. The Franklin site was
designed to alleviate flooding, infiltrating the entire water quality storm and the 25-year storm; however
site constraints (i.e. existing trees, narrow planter strips, the need for stormwater planters in a high foot
traffic area) did not allow HWA to allocate full storage of the water quality storm as required by the
COSM to store the water quality storm for those times when it's raining while the ground is frozen. Bear
Creek, on the other hand, required deeper basins to receive runoff from pipes crossing Bear Creek
Road . Therefore, Bear Creek has excess storage that meets the COSM requirements and is expected
to infiltrate any storm it receives, including the 100-year storm.
Snow: Monitoring snow events is outside the scope of this monitoring question and equipment and
methodology suggested below cannot be used; another methodology would be needed if the city
wanted to know more about cold weather performance. Nonetheless, it will be useful for maintenance
staff to know that in the experience of stormwater practitioners in numerous snowy areas of the U.S,
snow has been plowed into these facilities without impacting facility effectiveness or plant growth1.
Evaporation: Evaporation and evapotranspiration (i.e. evaporation from plants), especially in such a dry
and windy environment, is likely to play an appreciable role in reducing runoff; however measuring
evaporation is beyond the scope of this monitoring plan. If the City wishes sometime in the future to
monitor for evaporation, the most effective method would be to install a weighing lysimeter in a future
facility.
Hypothesis
The Bear Creek facilities are designed to store and infiltrate storms in excess of the 100-yr, 24-hour
design storm for non-frozen ground conditions. During frozen ground conditions the facilities can
overflow and cause mild flooding in storms that exceed the 2-yr, 24-hour design storm. Maximum
1
This is based on experience from various respondents on the EPA's npsinfo listserv after a question was asked
about the effect of snow plowing activities on bioinfiltration performance.
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ponding depth for the same size storm will be more shallow over time, then level off, as plants establish
and infiltration rates increase.
Basis for Hypothesis
Numerous studies have found bioinfiltration facilities to be very successful at reducing runoff through
infiltration and evaporation/transpiration; however, frozen soil during the winter will prevent infiltration,
which may reduce the effectiveness. Modeling was performed to estimate stated storm frequencies.
Monitoring Element
Maximum depths of water to within 0.1 foot accuracy. This is achieved by measuring the distance from
the measuring point to the top of the powdered cork (which is in a clear polyethylene tube and will stick
to this tube after water levels drop, as described in further detail below).
Monitoring Method
Monitoring consists of visiting the site in between storms of interest (defined below in Data Collection
Frequency and Duration) and observing and recording the height of the powdered cork.
At Bear Creek, we recommend monitoring Pond A since this facility will be the subject of MQ3, which
will count plants. In the experience of many in the Pacific Northwest, more plants and more plant matter
(aka biomass) results in higher infiltration rates, which will result in lower maximum ponding depths.
Since different basins have different drainage areas, it would be interesting, but not entirely necessary
to monitor this in each of the bioinfiltration ponds to see the variation, especially if one pond is located
on native soil and one on fractured bedrock.
The Equipment Needed and Data Collection Procedure below are excerpted and adapted from a USGS
publication found online at:
http://pubs.usgs.gov/tm/1a1/pdf/GWPD9.pdf2
(see Appendix D for original document), which
was developed as a way to monitor fluctuating
groundwater well levels.
Equipment Needed
First time only:
 4x4 untreated wood post
 Cement to hold post upright
 Plumb bob or level
 Transparent 3/8" polyethylene tubing
 Powdered cork, several pinches
 Brass tubing, 1/4-inch inside
diameter
 Non-lead shot pellets
 Hammer and nails (Bear Creek)
 Screwdriver and concrete screws
(Franklin)
 Hacksaw
Figure 7 Maximum Water Level Device (adapted from
USGS)
Return visits:
 Graduated steel tape
 Pencil or pen, blue or black ink.
Strikethrough, date, and initial errors;
2
excerpted from Groundwater technical procedures of the "U.S. Geological Survey: U.S. Geological Survey
Techniques and Methods" in bibliography, Appendix D
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

no erasures.
Monitoring log
Safety equipment: gloves, safety glasses, first-aid kit
Data Collection Procedure
Water Quality Considerations:

Do NOT use treated lumber for the post, since even environmentally sound lumber
treatments are likely to introduce pollutants such as copper (toxic to aquatic life, even in small
amounts) into the facility. Adequate durability should be achievable for our purposes using
untreated lumber set in a concrete footing, as shown.

Since concrete can change the pH of water during construction and impact plant health,
construct this device during the summer, when the concrete will have plenty of time to cure.
Once cured, unless it crumbles later, concrete will not change the pH of the system.
1. First time only: Install the post by digging out a hole at very low point of the facility, pouring in
concrete (mixed per manufacturer's directions on bag), and placing the post upright, using a plumb bob
or level. Minimize the amount of concrete needed and do not leave any excess material in facility once
post is upright.
2. First time only, construct the device:
a. The maximum water-level device consists of a length of transparent 3/8-inch polyethylene
tubing, two lengths of 1/4-inch inside diameter brass tubing, non-lead shot, powdered cork, and
a nail.
b. Crimp one end of an 8- to 12-inch length of brass tubing, slot the brass tubing with a hacksaw
over the lower 3/4 of its length, fill the brass tubing with non-lead shot, and attach it to the lower
end of the polyethylene tubing. Be sure to place enough non-lead shot in the polyethylene tubing
so that the tubing hangs taut and contains no kinks.
c. Put several pinches of powdered cork in the polyethylene tubing.
d. Bend a short length of brass tubing to form an elbow and insert the brass elbow into the
upper end of the polyethylene tubing.
e. Insert a nail on the side at the top of the post, as shown, to use as a measuring point.
f. Suspend the maximum water-level device by hanging the brass elbow over the measuring
point nail.
3. Each return visit after a storm: Determine the maximum water level. The powdered cork adheres to
the walls of the polyethylene tubing as the water level in the pond rises, thereby marking the maximum
water level.
a. Measure the distance between the measuring point and the top of the powdered cork with a
graduated steel tape.
b. Record the maximum water level on the monitoring log. (Accuracy of this method is to within
0.1 foot = 1.2 inches).
c. Calculate the ponding depth on the monitoring log.
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d. Shake the powdered cork to the bottom of the device.
4. Each return visit: Determine the rainfall depth (acceptable data sources described above) and enter
this on the monitoring log.
Data Collection Frequency & Duration
To rigorously answer the question of how effective these facilities are in managing stormwater runoff
from a wide range of events, data collection should be performed after every water quality storm or
larger (i.e. major storm) for at least the first two years, to create baseline of data for comparison. Plants
will be establishing during the first year, so this is the logic for the rigorous evaluation in the first two
years.
Less rigorous observation, when other maintenance activities are being performed or after unusually
large or intense storms will still provide insight into how well the facility is performing to reduce runoff.
Data can also be collected as desired, with the understanding that the measurement will reflect the
depth the water ponded during the largest storm event since the previous measurement (and the last
time the cork was shaken back down to the
bottom). In other words, if Bend experienced
a 1.5-inch storm and then a 1-inch storm
before going back to measure the cork
height, data would be collected for the 1.5inch storm, but nothing could be surmised for
the 1-inch storm.
Due to the annual variability in the weather,
this monitoring effort should be conducted for
at least 10 years, but if this is not desired,
continue this monitoring for as long as MQ2
is investigated, since these two questions are
very closely interrelated.
Data Interpretation & Adaptive
Management
The smaller the distance measured between
the measuring point (i.e. the nail, which
should be placed about 6" above the top
elevation of the facility) and the cork stuck to
the transparent tube, the higher the ponding
depth. This higher ponding depth should
correlate to a larger storm event than larger
measured distances from the nail to the cork. Figure 8 Example of how to interpret powdered cork
If, over time, the ponding depth is high, even level as ponding depth
during small storms, the facility may be
clogged. Perform full facility infiltration testing using water from a hydrant or water truck per MQ2
guidance to determine whether the facility infiltration rates are going up or down.
Being able to correlate ponding depth to the storm size will help us understand which storms, in reality,
are not fully ponded in the facility, but which generate outflows via the top of the facility. The table
below summarizes the results of modeling3:
3
using SBUH Type I 24-hour design storms
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Ponding Depth Predicted by Model
[feet]
Storm
Frequency
Storm Size
[inches]4
Bear Creek
BB-A
Bear Creek
BB-B
Bear Creek
BB-C
WQ (6-month)
1.0
0.7
0.6
0.7
2-year
1.5
0.9
0.8
0.9
10-year
2.0
1.5
1.3
1.2
25-year
2.5
1.6
1.4
1.3
50-year
2.8
1.8
1.6
1.4
100-year
3.0
1.9
1.7
1.5
Using the scatter plot that includes a trend line provided in the accompanying Excel file, plot data
recorded on the monitoring logs (x-axis: storm size [inches], y-axis: ponding depth [tenths of a foot]) for
each facility with a maximum water level device. Compare this against the ponding depths predicted by
the model. If ponding depths are lower than the ponding depths predicted by the model, then the facility
is performing better than expected. If ponding depths are higher than predicted by the model, then the
facility isn't performing as well as predicted by the model. No particular action needs to be taken in this
case. If performance is very poor, threshold criteria in other monitoring questions will be triggered.
Perform necessary actions as defined under these other monitoring questions.
Additional Considerations
Assumptions:


The tested infiltration rate of these facilities per MQ2 has not fallen below the baseline
The facility was built to within 5% of the shape designed. Ponding depths may vary because
the infiltration rate is greater or less than was modeled (5 inches/hour was assumed at Bear
Creek), but they may also vary because the facility was not constructed per plans, which is
very common according to one study performed at NC State5. The City should require the
contractor to provide complete as-builts to confirm that the shape that was constructed is
within 5% of the shape designed.
Available ponding storage may be reduced by leaf material.
To gather additional data and compare across facilities, the City may find it useful to set up monitoring
equipment in multiple ponds (Bear Creek) or cells (Franklin).
General Cost Considerations of Monitoring & Maintenance
The device is made of low cost materials commonly found in hardware/home improvement stores.
Some cost may be associated with the time to construct it if city staff perform this task. Monitoring can
easily be performed by volunteers. Graphing data will require it to be entered in Excel (see
accompanying Excel file with worksheet), but Excel will automatically graph the data.
4
Per Table 5-5 of the COSM
The author of this study from NC State could not be found online at the time of the writing of this narrative;
however, the author of this document saw this data presented at two different conferences in 2012.
5
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Most jurisdictions are concerned that if they don't clean out leaves and branches from their facility, the
ponding depth will be so affected that the facility won't work correctly. As long as the debris is not
diseased, leaving this material in a bioinfiltration facility is beneficial because:





It will serve as next year's nutrition for the plants
It will help insulate the roots from temperature swings
It will store moisture longer
It will save maintenance staff from having to fertilize the plants (commercial NPK fertilizers not
recommended for water quality reasons) or from spreading compost each year.
Leaves and branches will break down over time at different rates and also provide superior
habitat value for insects, which are the mainstay meal of birds and other creatures beneficial
to long-term watershed health and permeability.
At Bear Creek, there's plenty of depth and its location is more informal, so removing leaf and branches
may not be necessary. We suggest experimenting with maintenance activities here by leaving this
material in the basins until it reaches a depth of 6". If leaf litter breaks down fast enough, staff may find
that it never reaches of depth of 6". This will save a lot of time and money, and reduce trampling in the
bottom of the facility and subsequently reduce the risk of reducing long-term permeability and impacting
plant health. If the staff wishes to experiment in this way but only in one cell, choose Cell A where other
monitoring efforts from MQ4 will be estimating plant coverage and counting plants; it will be easier to
correlate biomass (the volume of plant material in the basin) to leaf and branch litter to estimate
necessary maintenance activities and costs in the future.
Snow plowing activities sometimes include hauling large amounts of snow to an off-site storage area.
The bioinfiltration facilities provide additional storage for snow that may reduce hauling costs and time.
In addition, storage of snow in bioinfiltration assures treatment, whereas storage on a paved yard or in
a landscape area that drains to the river may not.
Monitoring Question 2: How does permeability vary with time & season?
This is a question that is best answered on a facility-wide basis via flood testing; however, access to
water via a hydrant or water truck may be unfeasible for the Bear Creek site; therefore, two monitoring
alternatives are proposed, facility flooding and double-ring infiltrometer testing.
Overview
Permeability is a measure of the time water takes to soak into the ground and is measured with
an infiltration test. Permeability itself is not area dependent. Infiltration testing is a direct
measure of the soil’s capacity to convey water, measured in inches of water depth infiltrated per
hour.
Hypothesis
Long-term permeability will increase.
Basis for Hypothesis
This hypothesis is based on observations from two studies in Portland, OR. Tom Liptan
(Sustainable Stormwater Division of Portland’s Bureau of Environmental Services) has
observed the SE Division New Seasons bioinfiltration facilities in the public right-of-way for at
least 5 years and has noted an increase in permeability. These facilities have no pre-treatment
for sediment. Since the Franklin Street and Bear Creek facilities all have pre-treatment
structures, we expect a similar, possibly even better, result.
The second observation was by Ted Hart, a graduate student at Portland State University, who
did a study of the habitat value of vegetation roots. Ted evaluated the number of soil animals in
the soil directly underneath a plant and just next to the plant in bare soil. He found that there
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was much more biological activity/life in the soil underneath the plant. Since soil animals such
as earthworms and beetles are known to create and preserve soil structure, creating beneficial
voids as they move through the soil, Ted’s informal observations indicate that the more roots
there are in a bioinfiltration facility, the more beneficial soil life there will be, which would reduce
maintenance requirements by naturally preserving the long-term permeability.
Monitoring Element
Monitoring will be of the engineered soil starting at the surface of the facility (or underneath the
mulch if that option is employed and), which continues down in both facilities to a minimum
depth of 18".
Monitoring Method, Alternative 1: Infiltration Testing by Facility Flooding
If the facility has large areas of bare dirt, this method could cause the facility to clog by suspending fine
clay particles that settle out into an impervious sheen. Consider using Alternative 2 below in this case,
until plants are established (i.e. at least one growing season).
Alternative 1: Equipment Needed
 Watering truck, fire truck, or hydrant with a flow meter
 Yardstick
 Plumb-bob
 Timer
 Measuring device (ruler, measuring tape)
 Monitoring logs (see Appendix A) and writing utensil or computer
Alternative 1: Data Collection Procedure
Flood the facility to measure the facility-wide, overall long-term permeability of the facility as
follows:
1. Arrange for access to a measurable, flow-metered water source such as fire truck, watering
truck, or hydrant. Use of a hydrant may require a permit.
2. Embed yardstick into the facility to a depth of 2”, using plumb-bob to ensure yardstick is
plumb.
3. Begin adding water to facility at a known flow rate and start timer. When ponding begins,
record how much time has passed.
4. Fill until water level on yardstick reads 14” (which equates to a facility water depth of 12”).
Record time. (If facility is accidentally filled to a depth greater than 12”, note water depth.
Pressure head affects infiltration rate, so record time when water depth drops to 12”, which will
be the 14” mark on the yard stick, and then continue monitoring.)
5. Observe facility until it empties and record time when facility is completely empty.
6. Calculate facility infiltration rate by converting measurement from step 5 in minutes and
seconds to hours. Divide 12 by this number to find infiltration rate in inches per hour and record.
(Example: facility takes 5 hours to drain 12 inches, so 12/5 = 2.4 inches/hour.)
Important! Do not perform infiltration testing in the rain or within 24 hours after a major storm.
Monitoring Method, Alternative 2: Double-ring Infiltration Testing
Alternative 2: Equipment Needed
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
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
A double-ring infiltrometer: Two impermeable cylinders with an inner ring no smaller than 4
inches in diameter and equal to 50 to 70% of the outer ring diameter; for example, use an 8inch inner ring with a 12-inch outer ring. Minimum ring depth should be 8 inches.
Water source
Timer
Measuring device (ruler, measuring tape)
Flat wooden board that covers diameter of cylinders to push the cylinders evenly into the
ground
Rubber mallet
Monitoring logs (see Appendix A) and writing utensil or computer
Alternative 2: Data Collection Procedure
Use a double-ring infiltrometer to measure the infiltration rate of the soil. The following is a
modified excerpt from the 2011 Oregon Sea Grant publication “Infiltration Testing” on the
considerations and method for testing (Cah 2011).
Important! Do not perform infiltration testing in the rain or within 24 hours after a major storm.
Site preparation
1. Push plant material out of the way (preferred) or remove plants as necessary to install
rings as described below. Since the plants have a direct and beneficial effect on long-term
permeability, limit removal and root disturbance as much as possible.
2. Drive the larger outer ring in evenly, at least 2 inches (can be more, but make sure at least
6 inches of the cylinder is above ground) into the ground at the bottom of the facility by
setting the flat wooden board atop the cylinder and firmly striking it with the rubber mallet
(SEMCOG 2008).
3. Center the inner ring within the outer ring and follow the same procedure using the wooden
board and mallet. Make sure the bottoms of both rings (underground) are at the same depth
(SEMCOG 2008). Make sure the rings are easily accessible and that water can easily be
added over a period of hours (BES 2008).
Presoaking
4. Before beginning the infiltration test, the test area must be presoaked and a
measurement interval time established. To presoak the area, fill the inner and outer ring to
the brim or water level mark with water. Keep the water level above 4 inches for 30 minutes. At
the end of 30 minutes, refill the rings completely.
5. Note the water depth in the inner ring if it is not full to the top and wait another 10
minutes and then measure the water depth again to determine the drop in water level. If the
drop is less than 2 inches, use a 30-minute interval (SEMCOG 2008).
Testing
6. Fill the rings to the brim or up to a marked water level. Using the established interval times
and from the marked reference point, measure and record the water level drop in the inner
ring at each interval. After each recording, stop the timer, refill the rings and restart the
timer. When eight readings have been collected or the water-level drop stabilizes (when
the highest and lowest measurement within four consecutive readings is no more than a 1/4inch difference) no more measurements are required (SEMCOG 2008).
Infiltration rate
7. Determine the infiltration rate by averaging the measurements taken during the stabilized
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rate, expressed in inches per hour (SEMCOG 2008).
Restore vegetation
8. If vegetation was disturbed or removed to install testing equipment, restore soil to original
grades, replace plants, stabilize soils, and perform other activities to restore testing area to its
original state to the greatest extent possible.
Data Collection Frequency & Duration
Once, just after construction, and then once every three months (one per season) afterward for
at least 10 years.
Data Interpretation & Adaptive Management
There are three important infiltration rates to compare against:

Baseline: The initial testing performed just after construction should yield an infiltration
rate of at least 5 inches/hour at Bear Creek and 12 inches/hour at Franklin.

The design infiltration rate, which is the minimum infiltration rate that will pass the water
quality storm, is 0.001 inches/hour at all ponds at Bear Creek, or infiltrate the 25-year
flood storm at Franklin: 0.75 inches/hour in Franklin A, 0.36 inches/hour in Franklin B1
through B8, and 0.43 inches/hour in Franklin B9 through B12.

Tested field: The infiltration rate found during the monitoring process, which may go up
or down, but should never be less than the design infiltration rate.
See Figure 9 for a flow chart of activities and interpretations.
Additional Considerations
1. This monitoring effort also informs Monitoring Questions 3, 4, & 5.
2. Since worms, beetles, and other soil dwelling bugs prefer to dwell within the root structure
of plants where microbes on the roots are most numerous and because these larger soil
bugs need air and water, they move regularly through the soil to aerate it. In other words,
the more plants, with deeper, healthier root structures, the more aeration the soil will
receive. The more aeration the soil receives, the less likely it will be to clog, making the
facility easier to maintain.
Items that may impact or change conclusions of the double-ring infiltrometer approach are as
follows:
3. Since infiltration testing with a double-ring infiltrometer is not as site dependent as the
flooding alternative, if double-ring infiltrometer testing is implemented at the Bear Creek
site, then for comparison, it should also be performed at Franklin. This may help provide a
long-term correlation between the two methods that would allow a less water intensive,
more sustainable monitoring approach to be used in the future.
4. Since flooding is the preferred way to test system performance, it is recommended to
perform this in addition to double-ring infiltrometer testing, when possible.
5. Plant disturbance may impact overall, long-term function of the facility. Without careful
replanting of testing area, the monitoring itself could be a cause of erosion and clogging.
General Cost Considerations of Monitoring & Maintenance
 Man-hours: Infiltration testing for these facilities is expected to take between 4 to 8 hours.
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This monitoring element requires an inspector to visit the site after every major storm, but
since this is a recommended maintenance practice, the man-hours to visit the site would be
needed regardless of monitoring.

Equipment: The City of Bend already owns all the equipment needed.

Training: Training on proper methods for infiltration testing should be completed before
monitoring starts.
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Baseline is assumed to
be 5 inches/hour at Bear
Creek and 12 inches/hour
at Franklin. Native and
engineered soils must
meet this baseline.
Minimum Infiltration Rates
[inches/hour]:
Bear Creek: 0.001
Franklin A: 0.75
Franklin B1-B8: 0.36
Franklin B9-B12: 0.43
Figure 9 Flow chart to interpret data and adaptively manage at Bear Creek
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Monitoring Question 3: How do bioinfiltration facility maintenance practices
affect plant health?
Overview
The question focuses on how maintenance practices affect plant health. See the Maintenance
section of this Stormwater Monitoring and Maintenance Plan above and Appendix C, for specific
recommended practices. This monitoring effort is intended to give the City a general idea of how
healthy and numerous the plants are. Ascertaining detailed information of health and diseases
is outside the scope of this monitoring plan; however number of species as indicated by the
counts and growth over time as indicated by the photos should provide the City with a measure
of plant vigor.
Hypothesis
Generally, plants will benefit from implementing the recommended practices and frequency of
the Maintenance Section and Appendix C. Plants may be impacted by application of the deicing
agent, Magnesium Chloride (MgCl2).
Basis for Hypothesis
Maintenance practices are designed to protect plant health.
Monitoring Element
Vegetation height, spread, & count.
Monitoring Method
Photo point monitoring, plant & weed species count, and plant health assessment. (See also,
the approach described to monitor long-term permeability under Monitoring Question 2 above,
which will also be needed to assess the source of a problem if plant health declines.)
Equipment Needed















Figure 10 Homemade clinometer to ensure
that photos are taken at the same angle, year
after year.

3/8” diameter rebar pins or fence
posts
Mallet or hammer
Weather and waterproof labels
Photo point monitoring forms
Site identification card
Camera (digital preferred)
Tripod
Stadia rod
Plumb bob
100 foot measuring tape
Compass
Clinometer (Figure 10)
Dry erase marker
Metal detector (optional)
Water based spray paint (optional),
meeting ODOT striping paint
specifications
GPS unit (optional)
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Data Collection Procedure
Preparing the Site
1. Install the 3/8” diameter rebar pins or fence posts in the locations shown below for each site.
(Where possible, camera points were located in safe locationsover points at which future
infrastructure like catch basins and sidewalks have a unique intersection or corner. For instance
CP-BCR-A1 and CP-BCR-B1 are to be positioned over the southeast corner of the catch basin
inlet; CP-BCR-C1 is at the southwest corner of a curb tight triangle of sidewalk. Other camera
points in landscape areas will need rods.) Rods may be driven into the ground if a metal
detector is available to find them again (preferable), or may be left above ground. If left above
ground, rods or fence posts may be painted a bright color (off-site using any appropriate air and
water quality source controls) to make them easier to find, and make sure that the height will not
cause a tripping hazard. Mark the spots with a GPS unit to make them easier to find, if desired.
Placeholder: This graphic will be created by City of Bend staff from the final designs
at Franklin to show all the locations of the camera and photo points with labels that
correlate to the form provided. Choose camera and photo points that will be safe
and unobstructed by the future growth of the vegetation or existing infrastructure.
Figure 11 Recommended Camera & Photo Points on Franklin Street
Figure 12 Recommended Camera & Photo Points at Bear Creek Road
2. Attach water and weatherproof labels (metal preferred for durability & sustainability reasons)
labeled with the camera and photo point numbers to the appropriate rods.
Preparing to Take Photos
3. Print out Site Identification Card – blue paper has the best visibility – and laminate it.
Complete the form using a water based marker and attach this to the corresponding photo point
rod.
4. Print out photo point monitoring forms provided (in either pdf format or from Excel sheets),
one each for Franklin & Bear Creek, for each site visit.
Taking Photos
5. Fill out the Site Identification Card and take a photo of it.
6. Set up tripod so that the bottom of the lens is 4.5 feet above finish grade of the camera point
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rod or other location as indicated in Figure 11 and Figure 12.
7. Use compass to set direction of lens per the Photo Point Monitoring Log.
8. Use clinometer to match “Angle down to Photo Point” per the Photo Point Monitoring Log.
For Bear Creek, since I wasn't able to go visit the site, the best angles will have to be developed by
Bend staff. My intention is that CP-BCR-A1, CP-BCR-B1, and CP-BCR-C1, each pointing to two photo
points across the street will probably be level or close to level. CP-BCR-A2, CP-BCR-B2, and CP-BCRC2 will all point down, approximately to the bottom of the photo point rod. When the facility is built
though, you may feel differently about where these points will best be located from, to, and angled,
especially if the planting plan was changed during construction, which is common.
9. Using a digital camera, be consistent with using the following settings:

Auto Mode. A decent camera should do an adequate job of choosing the best settings
for the conditions.

Zoom set 1X, so that the picture looks as far away as possible.

For repeat photos, point the camera toward the photo point and compare with the photo
entered on the last field visit’s form.

Resolution should be set to at least 3 Megapixels, but higher resolutions will make detail
easier to see later, should a researcher wish to “blow up” a photo.
10. Attach the stadia rod to the posts at the photo points, using the plumb bob to ensure it is
plumb.
11. Take the photo. If using a digital camera, check the preview screen to make sure it’s not
blurry or that cars driving by aren't included in the photo.
12. Repeat steps 5 to 11, as needed (some photo points will have the same camera point) until
all photos have been taken.
Other Observations
13. Complete the Vegetation Monitoring Form.
Recording Data
14. Copy the photos to a file folder (on a computer in a pre-designated and agreed upon
location specifically for monitoring data) and rename with the following format:
[Date (Year first, then month & day)] [Photo Point #]
Example: 2011-07-24 PP-BCR-A1
Putting the year first will keep years of data together, so that progressions will be easier to look
at by photo preview programs. Don’t rename the last three letters identifying whether the photo
is a jpg, bmp, etc.
14. Insert digital photos into the Photo Point Monitoring form in Excel. This is the form that
should be printed out for the next site visit to compare against when setting up the camera.
Data Collection Frequency & Duration
To monitor the effect of maintenance on plant health: Once right before (within a week of two)
and once right after (within a week or two) of scheduled maintenance activities directly related to
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the plants, such as pruning. Perform for at least 10 years.
To monitor overall plant performance: Once a year, for at least 10 years, during late spring,
ideally between Jun 1 and Jun 20, when plant identification will be easiest.
Data Interpretation & Adaptive Management
If during monitoring, other photos such as close-ups are needed and added to the photo points, note on
the forms where they first appear and ever after deviations from the settings recommended above.
As long as plants are not shrinking or become less numerous over the monitoring period, the
plants in the facility can be considered successful. Considering the numerous environmental
and social impacts these facilities may receive, assessing plant vigor is fairly straightforward,
but attributing poor health to either one or another maintenance practice is much more difficult.
In addition, these facilities will experience various unobservable environmental and social
impacts, such as hail, children picking flowers on their way to school or neighbors letting their
dogs use the facility to relieve themselves. Identification of factors attributing to poor plant health
is beyond the direction of this manual; however additional resources are provided below.
Pruning, except to create clear lines of sight to improve safety, probably won't be needed much
at this site, unless the neighbors think that the new development is more unsightly than what
currently exists and start to complain, so before and after maintenance photos may not show
much change. Still, no change after maintenance indicates that pruning really was not
necessary and this will help the city assess maintenance costs for future facilities in similar
areas.
Depending on soils and whether maintenance staff stay on stepping stones or make an effort
not to walk within the facility, compaction could impact plant health. Testing performed while
implementing MQ2 should indicate whether soils have been compacted. Desire paths, which
will be dirt paths where plants can't grow, may also develop throughout the facility as a result of
performing routine maintenance activities and compacting the soil in the process.
If the existing ponderosa pine starts dropping limbs or dies a few years after construction, it's
roots may not have been properly protected from compaction and disturbance during
construction, for instance, if the contractor cuts a lot of roots to install the proposed wall without
the oversight of a certified (preferably by the International Society of Arboriculture) arborist.
Compaction under the dripline can be checked with an infiltration test. Roots can be
investigated if the tree is removed. In summary, maintenance activities may not have played a
role in impacting this particular plant's health in this case.
Excessive ponding, as discovered during implementation of MQ1 could indicate that the facility
is not draining as expected. This could mean:
1. If excess sediment bypasses the pretreatment sumps, then it could theoretically
smother the plants by blocking root's access to air, and even water if sediment is
keeping the facility from draining at all. However, in a review of a number of 10-year old
facilities throughout the Portland region, even those that were not considered to have
proper maintenance performed or that had no pretreatment, sediment was not found to
be a factor in clogging. It may be that the fear of clogging is greater than the actual
incidence of clogging; however, if the facility is not draining at the surface and a
substantial depth of sediment is found (i.e. greater than 3"), plant health would definitely
suffer from lack of access to water. Remove sediment by hand to the maximum extent
practicable and loosen the rest and test the infiltration again. If the facility drains after
this, then sediment can be assumed to have impacted plant health.
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2. Subsurface clogging could be the cause of waterlogged plants. In this case, water
wouldn't be draining out the bottom, saturating the soil and keeping the plants in a state
of "wet feet". While plant species in these facilities usually have some wetland status
indicator associated with them (i.e. FACU, meaning "Facultative Upland"), they are
unlikely, in any facility to have an OBL, or "Obligate" status, which would allow them to
live with perennially "wet feet".
OPTIONAL ANALYSIS: If digital photos are taken with care, consistently over time with a plumb
stadia rod in the photograph, there are three graphical methods for measuring growth, if the city
decides it would like to have more detailed information. These methods are:
1. A graphical method has been successfully used by the USDA and outlined in the "Photo
Point Monitoring Handbook: Part B -- Concepts and Analysis"
(http://www.fs.fed.us/pnw/pubs/gtr526/gtr526B1.pdf). In this method, 8x10 photos are printed,
plant outlines are traced by hand onto a clear plastic like that used for overhead projectors, then
overlaid on a grid so the area of plants can be approximated.
2. Digital photos can be imported into Photoshop. The photo on the top layer can be made
transparent and aligned with a photo of the same photo point. Area is not really easily estimated
in Photoshop, but a qualitative comparison can be seen regarding whether the plants have
grown or not since the last photo.
3. Digital photos can be imported in AutoCAD or some other vector program. Plant outlines can
be digitized from one time period to the next. Areas and differences in areas can be easily and
automatically calculated. Overlaying the outlines using different layers also makes it easy to
observe qualitatively.
Additional Considerations
1. Stepping stones should be placed in the facility. If these turn out to be too few or in the
wrong place to accommodate maintenance activities, the soil could be compacted by foot
traffic. If soil is compacted, plant health will likely be impacted, so care should be taken to
“stay on the path” and add a few more stepping stones as needed. Larger stones will
spread out the weight and reduce compaction better than small stones.
2. If the pins or fence posts are left sticking out of the ground, birds perching on them may
increase fertilization of those areas (GCCBC, 2009), which may cause plants in the
monitoring areas to grow faster than plants outside the monitoring area. It may increase the
biological pollutant loading of the facilities.
3. Imprecise measurements, time of year, and rare events can impact interpretation of data.
For instance, if blooming times are significantly different in one year from another, this may
make it more difficult to assess which and how many plants are in a facility.
4. Consistency in tripod setup, direction, angle, etc is necessary to collect meaningful data,
year after year. Photo point monitoring is often performed by different people, such as
rotating interns, each year, so make any additional notes that will help others take
consistent photos.
5. Plant health may be affected by a number of phenomena unrelated to direct maintenance
activities inside a bioinfiltration facility.
a. Magnesium Chloride (MgCl2) Deicing Application: The Colorado State University
Extension's fact sheet "Magnesium Chloride Toxicity in Trees"
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(http://www.ext.colostate.edu/pubs/garden/07425.pdf) includes information on best
management practices for road applications, how to identify MgCl2 damage, and
sample collection for lab testing, in addition to other information. Specific toxicity
levels for trees both states have in common include the lodgepole pine, Ponderosa
pine, and Douglas fir. According to AASHTO
(http://environment.transportation.org/environmental_issues/construct_maint_prac/c
ompendium/manual/8_1.aspx) and other sources, trees and vegetation closer to the
road are likely to suffer more damage than vegetation farther away.
b. Insects: While some insects are pests that will impact the health of the facility, one
of the benefits of native plants is that they support the life cycle needs of native (and
some non-native/generalist) insects. Insects are the foundation of the food web -they are the main protein source for numerous birds and small mammals that
collectively provide our communities with ecosystem services like cleaner water, air,
and soil. Not all insects are pests that need to be removed from the plants. Use an
integrated pest management approach. First, identify the insect species present.
Second, decide if that species is actually harming the plant or is likely to harm the
plant; a little bit of leaf eating is good and will often not hurt a plant. Third, if removal
is necessary, identify the least environmentally harmful method of removal using
mechanical means. Pesticides should never be applied in bioinfiltration facilities
since these soluble pollutants easily move through the soil making their way to
ground and surface waters and will also unintentionally kill soil life beneficial for
long-term permeability.
c. Soil Mammals: Voles, moles, and other larger soil dwelling animals can aerate the
soil and provide additional storage in the watershed for rainfall until it infiltrates.
Removal of these animals from within or nearby the facility may not be in
accordance with the city's water quality goals and consideration to leaving them in
place should be given, depending on the extent of damage they are actually doing
to the vegetation.
d. Drought: Plants surrounded by pavement may have difficulty surviving without
occasional irrigation during hot spells. According to the fact sheet cited above, the
effect of drought on plant foliage may look very similar to damage from magnesium
chloride. Lab testing of dropped foliage can be used to determine the difference.
e. Overuse Access/Compaction: Depending on soils and whether maintenance staff
stay on stepping stones or make an effort not to walk within the facility, compaction
could impact plant health.
6. Effective photo point monitoring relies on decent photos. The best times of day to shoot
photos at Bear Creek is probably in the morning since most of the photos are pointing either
north or west. Don't take a photo directly into the sun.
Additional Resources:
 2012 Pacific Northwest Insect Management Handbook:
http://insects.ippc.orst.edu/pnw/insects
 Pacific Northwest Plant Disease Management Handbook (helps you to quickly narrow
diseases by plant species): http://pnwhandbooks.org/plantdisease/
 Pacific Northwest Weed Management Handbook: http://pnwhandbooks.org/weed/
 Oregon Department of Agriculture website: http://www.oregon.gov/ODA/PEST/ipm.shtml
 If you believe you must use pesticides, Oregon State University Extension's "Least Toxic and
Organic Pesticides for Gardeners":
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http://extension.oregonstate.edu/lincoln/sites/default/files/Least_Toxic_Pesticiddes_for_Gard
eners.pdf
General Cost Considerations of Monitoring & Maintenance
Photo point monitoring is an easy, effective, and cost-effective method for gathering information
on vegetation & changes in the ecosystem. (USDA Forest Service). It can be done by
volunteers and interns for very little investment in man hours. The other practice of counting
plants can also be done by volunteers who have some training in plant identification. An
illustrated handout picturing plants volunteers need to count would be very helpful..
If additional optional analysis to qualitatively or quantitatively assess plant vigor using methods
outlined above to compare traced areas on photos over time, many more hours are needed.
Monitoring Question 4: Is non-irrigated vegetation successful?
Overview (Bear Creek only)
The City of Bend will not irrigate vegetation at all, after the establishment period outlined in the contract
specifications. This question will save the city a substantial amount of money in time, water, and
irrigation infrastructure in the future if the establishment period is only ”through one full growing season
(through the fall of the year following installation)”6 and will also identify the most resilient plants for this
stormwater management application.
Hypothesis
Plant survivability will be high, monitoring after the irrigation period, and able to reach an ideal targeted
plant coverage of 90% within 3 years after planting. Some species will have a higher rate of survival
than others.
Basis for Hypothesis
Based on the author's conversation with the landscape designer, plant species were chosen because
they are aggressive spreaders with previous success establishing in similar conditions.
Monitoring Element
Live plant coverage.
Monitoring Method
Visual inspection to count live plants.
Figure 13 Designated Observation Area
Equipment Needed
 Monitoring logs and pencil or computer
 Planting plan
6
per project specifications.
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
Phone: Volunteers: if you see bare soil, contact City of Bend Public Works 317-3000. (Please also make
a note on the inspection sheet for follow up by city staff. )
Data Collection Procedure
For the Observation Area shown in Figure 13:
Establish a Baseline in the Observation Area
Immediately after planting:
1. Estimate and record the current percentage of area covered/shaded by the Idaho Fescue, which
should have been seeded at construction. (Imagine a photo taken from directly above the area;
estimate the percentage of area that is plant foliage (i.e. plant spread) and the amount of area
that is bare ground and mulch.)
2. Count and record the number of each plant species. When this monitoring plan was created, the
planting plan design called for the following species and number to be planted:
Plant Species – Plugs & Pots
Count
Native Blue Flax/ Linum Lewisii
[111]
Showy Penstemon or Salvia dorrii
[45]
Sulpher Buckwheat/ Erigonum Umbellatum OR Linear Leaf
Daisy/ Erigeron Linearus
[57]
Bluebunch Wheatgrass/ Psuedoroegneria spicata
[69]
Curl Leaf Mt. Mahogany
[3]
Big Leaf Sagebrush
[14]
Desert Sweet
[7]
[15]
Green Rabbitbrush
[2]
Ponderosa Pine
Plant Coverage Estimate
Percent
Idaho Fescue/ Festuca Idahoenses that was seeded plus all
the species above
[100%]
Since there are often discrepancies between design and construction, confirm that the above
table accurately represents the species that were really planted and in what number and enter
this data on the log provided, but also update it here as the baseline, so when volunteers or staff
go out to do a count with these instructions they know whether or not they’ve hit the threshold,
which I’m defining as 40%, being 50% less than the ideal coverage.
Perform Annual Site Visit in the Observation Area
3. Identify and count dead plants. In some cases, this will be obvious, but not all plants with no or
dried leaves are dead. If there’s any doubt, check a stem by gently bending. If it bends, it’s still
alive. If it breaks and is gray inside, it’s dead. If plant species is in question, identify it based on
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its location as shown in the planting plan. If plant species were moved during construction,
make a note on the planting plan copy and on the monitoring log.
4. Estimate and log areas of bare soil as might be seen if you were standing over the facility and
looking directly down. In other words, bare soil underneath the foliage of a plant is considered
stabilized, but bare soil outside the foliage where roots are less likely to be growing can be
mobilized by runoff flowing through the facility to become a stormwater pollutant.
Data Collection Frequency & Duration
Visit the site once a year in the summer for 10 years or until plant coverage declines to 40%. The best
time for people unfamiliar with the life cycle of native plants to observe and count plants is between
June 1st and June 20th; this is when all the chosen species should be "leafing out".
Turbidity (cloudy water) is caused by suspended sediment and is a water quality pollutant, but easy to
prevent with proper erosion prevention and sediment control measures. Inspections and maintenance
activities to control sediment should be done on a more frequent basis as indicated by the Maintenance
Plan and at least once a year (depending on the maintenance requirements of the chosen erosion
prevention and sediment control measures) at the beginning of the rainy season.
Data Interpretation & Adaptive Management
Usually, when plants die in a facility after the contract irrigation period, the maintenance plan will call for
them to be replaced in such a way that the plants cover 90% of the facility; however, this action will
negate this experiment because new plants will then have to be irrigated for another irrigation period.
Tracking which ones are new and which ones are not would make this monitoring effort overly
complicated.
So, in short, do NOT replace plants when they die until this monitoring effort is
discontinued by either one of the following two thresholds that trigger conclusions:
40% Minimum Coverage is Maintained for 10 Years
 If 90% of a particular plant species survives, this would be considered to be a resilient
species and could be used in bioinfiltration facilities in the future.

If more than 50% of any one species survives, this could be considered to be a somewhat
resilient species. If this species is intended to be used in the future, the design might
overplant this species, so that 90% coverage will be achieved.

If less than 50% of any one plant species survives, this plant should be considered
unsuitable for future use under these establishment conditions.
After 10 years, discontinue this monitoring question, replant if needed, and irrigate using best
practices for high desert areas that will ensure 90% plant coverage. The author recognizes that
irrigation is not desired; however, if plants in the facility fail, and the City concludes that lack of
irrigation was the cause of the die-off, perhaps an occasional watering, via the fire hydrant or an
alternative connection to the 6" water line, would be possible in light of the failure; otherwise, the
City should consider retrofitting this facility with a non-vegetated low impact development
alternative, such as sand filters (high maintenance) or soakage trenches (UIC required).
Coverage Falls Below 40% at Any Time
If at any point within the 10 years after the establishment period, plant coverage drops to less
than 40%, discontinue this monitoring question, replant, and irrigate using best practices for
high desert areas that will ensure 90% plant coverage. The author recognizes that irrigation is
not desired; however, if plants in the facility fail, and the City concludes that lack of irrigation
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was the cause of the die-off, perhaps an occasional watering, via the fire hydrant or an
alternative connection to the 6" water line, would be possible in light of the failure; otherwise, the
City should consider retrofitting this facility with a non-vegetated low impact development
alternative, such as sand filters (high maintenance) or soakage trenches (UIC required).
If, at the discontinuation of this monitoring question, total plant coverage is less than 90%, then the
strategy of using a short establishment period and not irrigating afterward can be considered
unsuccessful. We recommend that the City replace dead plants throughout the facility using the original
planting plan or a mix of the plants that were found to be resilient, as desired, and to irrigate the plants
as needed to ensure facility function and aesthetic goals.
Additional Considerations
 Since sediment is a stormwater pollutant of concern, plant coverage of 90% is often required by
the end of the 3rd year, so leaving a facility with bare spots that exceed 10% is not really
desirable, from a water quality perspective. Even if the facilities are not directly connected to a
waterway, wind picks up sediment and could carry it to an area that is directly connected to a
waterway. As plants die and soil is exposed, install sediment prevention and erosion control
methods that will be effective in flow-based facilities, which might include reinforced erosion
control blankets and wattles, per Figure 14.

As stated in Monitoring Question 2, plants and the soil animals that dwell in their roots work
together to create and preserve the long term permeability of a facility.
Figure 14 Erosion control against wind and water is important for protecting watershed health
General Cost Considerations of Monitoring & Maintenance
A budget should be allotted:

For the man-hours to count and log plants once a year

to install and maintain erosion prevention and sediment control measures appropriate to flowbased facilities for up to 10 years during monitoring,

for materials and labor to replace 60% of the plants, and

to establish the new plants with additional irrigation if 90% coverage is not achieved per
guidance offered above in “Data Interpretation & Adaptive Management”
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Monitoring Question 5: What is the maintenance cost and time needed?
Overview
City staff wish to track the maintenance cost and time needed to maintain the vegetated stormwater
management systems at Franklin and Bear Creek to develop a realistic budget for future facilities.
These systems have been intentionally and carefully designed to reduce maintenance over similar
systems in other places. For instance, before flowing into the vegetated stormwater facilities, most
runoff flows first into a catch basin with a sump, which will settle out sediment to reduce the incidence
of clogging within the facility and to provide a convenient and familiar way to remove sediment.
Hypotheses
Cost and time will go down over time.
Basis for Hypotheses
Basis for each hypotheses below corresponds to numbered hypothesis above.
1. Numerous studies have shown that the cost of maintaining green infrastructure is on par or
even lower than maintaining gray infrastructure. The latest is a report from the American Society
of Landscape Architects (ASLA), American Rivers, the Water Environment Federation (WEF),
and ECONorthwest entitled " Banking on Green: How Green Infrastructure Saves Municipalities
Money and Provides Economic Benefits Community-wide"
(http://www.asla.org/uploadedFiles/CMS/Government_Affairs/Federal_Government_Affairs/Ban
king%20on%20Green%20HighRes.pdf).
2. By the end of three years, plants are expected to be well established. In general, healthy plants
have been observed to increase infiltration rates, which prevents clogging and lowers
maintenance.
Monitoring Element
The time and cost of all maintenance activities performed on either the vegetated stormwater facilities
or on the areas draining to them should be monitored and recorded. These activities include, but are
not limited to, street sweeping, weeding, structure repair, pruning, etc. In cases where maintenance
activities that are needed were not caused by the vegetated stormwater facilities themselves -- for
example, curb damage that would've happened regardless of what was behind it -- this should be noted
on the maintenance log and not added up in the cost of maintenance.
Monitoring Method
Record time and costs at each facility and sum these up over time.
Equipment Needed
See the equipment needed under the Maintenance portion of this document.
Data Collection Procedure
For both the Bear Creek and Franklin sites, during inspection and maintenance activities:
1. Log start time for each of the groups of activities performed from the "Inspection & Maintenance
Checklists", adapted from the Central Oregon Stormwater Manual and included as Appendix C.
2. Perform inspection and maintenance procedures as required by the "Inspection & Maintenance
Checklists".
3. Log end time for each of the groups of activities on the "Inspection & Maintenance Checklists".
4. Add up time on all "Inspection & Maintenance Checklists" and log this into MQ5 Site Visit Log,
provided in Appendix C.
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5. On MQ5 Site Visit Log, summarize materials needed to perform maintenance activities and
estimate quantity.
6. Complete unit cost upon returning to the office if unknown while in the field based on actual
most recent purchase of material.
7. Add up all costs and enter as "Total Cost" at the bottom of the MQ5 Site Visit Log.
8. Summarize all time and costs using the MQ5 Summary Log, one for each site for each year.
Data Collection Frequency & Duration
Collect data for each site visit to either the Franklin or Bear Creek sites. If no maintenance is
performed, there will still be some time spent on inspection. Since vegetated facilities take up to three
years to fully function, monitor for at least 5 years and preferably 10 years. A longer monitoring duration
will offer insight into maintenance time and cost and account for turnover within the organization, which
can increase maintenance time and costs.
Data Interpretation & Adaptive Management
The way runoff flows into and throughout a facility or series of facilities is based on the design,
construction, and maintenance. Since most of the variables associated with the construction and
maintenance are unknown at the time of writing this narrative, it's possible that some elements of the
design will not behave as expected. Regardless of maintenance costs, some design modifications may
be helpful in reducing time and costs. To best identify problem areas, visit the facility during an array of
storm size events and note where water is flowing and not flowing. To discern whether a facility is
functioning as designed, the observer must first understand the design intent for these systems.
Detailed descriptions of how the facilities are envisioned to function, where water should be flowing and
when during a variety of storms, are as follows:
Franklin Avenue: Functional Description
Runoff from the intersection of NW Franklin Avenue and NW Lava Road from the crest at the
centerline of this road sheet flows to the curb and downhill in a northwesterly direction. When
runoff reaches the catch basin inlet in Stormwater Planter B in cell B1, it enters the curb
inlet/catch basin and drops into the sump. At the same time, runoff will be flowing into the curb
inlet/catch basin in cell B10, the curb inlet in cell B12, and Stormwater Planter A from Franklin
and also in cells B2, B7, and B12 on the sidewalk side of the planters. Water should not be
bypassing the curb inlets or curb cuts because the inlet is blocked by sediment build-up, trash,
or leaves. Water may be bypassing the curb inlets during intense storm events when an inlet
cell's ponding capacity has been exceeded and water is backing out of the system.
At the curb inlet/catch basins a sump stills the water, allowing some sediment to drop out and
the sumps continue to fill until the height of the water reaches the elevation of the slot (aka
weir), which has been cut out of the back of the curb inlet structure. After flowing over the slot,
runoff hits the energy dissipater/rock pad, which should be arranged in such a way to prevent
soil erosion around the edges of the rock pad. In the case of the curb cuts on the sidewalk side
and road side (cell B12), runoff flows directly in and hits the rock pad. (Runoff from vehicular
areas has a much higher amount of sediment than sidewalks.)
As runoff flows into the facility into the various cells, it infiltrates into the soil. If the duration or
intensity of the storm overwhelms the infiltration capacity of these cells, water will start to pond,
until it overflows. In Stormwater Planter B, this saturation, ponding, and overflow over the
partition walls continues down the hill until cell B12 ponds water to the height allowed by the
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partial curb cut at the street side. It will then crest the curb cut, flowing back out to Franklin and
into Stormwater Planter A, if this facility has any ponding capacity available.
Regardless of storm size, all ponded water should be gone -- infiltrated into the uncompacted,
native subsoils below -- within 72 hours (3 days) of the storm event.
Bear Creek: Functional Description
Runoff from both sides of Bear Creek enters the bioinfiltration basins from the intersection of
Cravens Road to Cessna Drive. During a rain event, runoff from the south side of the road
enters either one of the two curb inlets or one standard catch basin with a sump where
sediments settle out. When water ponds in the sump to a depth of approximately 18", it
overflows into a pipe to outlet at a concrete pad and rip rap located at the bottom of each basin.
Runoff from the north simultaneously enters catch basin inlets, also with sumps, but water
ponds in the bottom until it reaches the elevation of the slot (aka weir) in the top, back of the
curb inlet and flows out onto a rock pad at the top of the basin. Water flows down the side of the
basin over the rock until it reaches the bottom, joining runoff from the south. While the storm
duration and/or intensity is low, runoff will infiltrate right into the native soils and fractured
bedrock below. As the storm duration and/or intensity increases, ponding begins when native
surface soils are saturated and the rate of inflow exceeds the rate of infiltration. When a storm is
really long and intense, on very rare occasions, water will back out of the catch basins on the
south side of the road and runoff will flow downhill, following street grades.
Regardless of storm size, all ponded water should be gone -- infiltrated into the uncompacted,
native subsoils below -- within 72 hours (3 days) of the storm event.
Additional Considerations
City staff might also consider the value of these stormwater systems to meet regulatory requirements
and provide social benefits. For instance, a program where volunteers work to maintain these sites
would help the City of Bend meet the six minimum requirements under their Phase II NPDES (National
Pollutant Discharge Elimination System) and also serves as a community building effort.
Future capital improvement projects that might be avoided as a result of these systems are also a
valuable way to offset the costs of these systems. For instance, avoided infrastructure costs at Franklin
would include catch basins and sewer extensions to drain Franklin during a flood.
If the City wishes to accurately compare "green" against "gray" infrastructure costs, costs and time for
current maintenance, in addition to future maintenance, at both sites must be tracked. The City already
has a method for tracking maintenance, but not on a such a small scale, so maintenance activities
should be prorated to reflect the linear feet of road managed by each site, which is as follows:
If the City wishes to compare gray to green infrastructure costs, update the table below to reflect the
way you track maintenance activities currently.
Facility Location
Manages:
Linear feet
Total linear feet
Bear Creek
Franklin
General Cost Considerations of Monitoring & Maintenance
Some maintenance activities including periodic weeding, pruning and trash removal could be performed
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by volunteers with appropriate safety gear, preferably led by a crew leader familiar with this
maintenance and monitoring plan and who is able to identify weeds and teach proper pruning
techniques.
Maintenance activities that should be performed by City staff include:







Any activities that may impact flows into or out of the facility (i.e. sediment removal, pruning
plants at inlets, putting rock pads back in place)
Sediment removal and disposal
Soil stabilization and any other erosion prevention and sediment control implementation
Pipe, curb, wall, or any other structural repair or replacement
Any adaptive management decisions that occur from efforts to reduce costs or time spent
Tree removal
Removing standing water (i.e. Defect: Mosquito Breeding Vector)
Appendix A – Monitoring Data Recording Forms
Forms are available in Excel format. Please see Excel Workspace documents titled "Monitoring
Logs.xlsx". To help with entering data, blue highlights indicate what data should be entered. White
fields are either headings or fields that will calculate automatically when data has been entered.
Instructions for setting up the logs and entering data are in italics.
Forms may be printed out and brought to the field, but keeping all the data together in one place in
Excel files is preferable since this will make future analysis much easier.
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Appendix B -- Worksheets for Data Analysis
Some worksheets have been developed to help the City enter and analyze so that conclusions can be
drawn and adaptive management strategies can be employed as needed. Charts will adjust themselves
to new data.
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Appendix C -- Maintenance Requirements from the Central Oregon Stormwater Manual
Inspection and Maintenance Checklist
Conveyance Systems (Pipes & Ditches)
Property Address: ________________________________________________ Property Owner: ______________________________
Treatment Measure No: _____________ Date of Inspection: _______ Type of Inspection: U Pre-rainy season U Monthly U Quarterly
U Annual U Re-inspection 1
Inspector(s): _________________________________ Start Time:_____ End Time: ______
Defect
Conditions When
Maintenance Is Needed
Maintenance
Needed? (Y/N)
Comments (Describe maintenance
Results Expected When Maintenance Is Performed
completed; and if any needed
maintenance was not conducted, note
what is needed and when it will be done)
Pipes (Bear Creek only)
Sediment
and Debris
Accumulated sediment
exceeds 20% of the diameter
of the pipe or 20% of the
openings in a debris barrier.
All sediment and debris removed from the pipe and/or
debris barrier.
Vegetation
Vegetation that reduces free
movement of water through
pipes.
All vegetation removed so water flows freely
through pipes. Stabilize any bare soil resulting from
maintenance activity.
Damaged
Pipe
1
Pipe is repaired or replaced. Stabilize any bare soil
resulting from maintenance activity.
Protective coating is
damaged or rust is
causing more than 50%
deterioration to any part of
pipe.
Any dent that decreases
the flow area by more than
20% or puncture that
impacts performance.
Re-inspection of a previously-noted maintenance issue.
[[== Insert Agency Name ==]]
Page 1
Central Oregon Stormwater Manual
C:\Documents and Settings\willg\Desktop\COSM\App 12B\ConveyanceSystem Chklst.doc
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Conveyance Systems Inspection Checklist
Inspection Date: _________________
Property Address: _________________________________________________________________________ Facility Name/Designator: __________
Defect
Debris Barrier
Conditions When
Maintenance Is Needed
Maintenance
Needed? (Y/N)
Comments (Describe maintenance
Results Expected When Maintenance Is Performed
completed; and if any needed
maintenance was not conducted, note
what is needed and when it will be done)
Barrier is replaced or repaired to design standards.
Barrier is firmly attached to pipe. Bars are in place
with no bends more than 3/4 inch.
Debris barrier is missing
or not attached to pipe.
Bars are bent by more
than 3 inches.
Bars are loose or rust is
causing 50%
deterioration to any part
of the barrier.
Open Ditches (i.e. Conveyance from Bear Creek Curb Cuts)
Trash and
Debris
Trash and debris is cleared from ditches.
Trash and debris
accumulated in ditch.
Visual evidence of
dumping.
Sediment
Accumulated sediment that
exceeds 20% of the design
depth.
Sediment removed and discarded of properly. Ditch
cleansed of all excessive standards sediment and
debris so that it matches design.
Vegetation
Excessive vegetation that
reduces free movement of
water through ditches.
Water flows freely through ditches.
Erosion
Damage
to Slopes
and
Channel
Bottom
Eroded damage over 2
inches deep where cause of
damage is still present or
where there is potential for
continued erosion.
Slopes should be stabilized using appropriate erosion
control measure(s); e.g., rock reinforcement, planting of
grass, compaction.
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Inspection and Maintenance Checklist
Energy Dissipaters (Bear Creek & Franklin)
Property Address: ________________________________________________Property Owner: ______________________________
Facility Name/Designator: ___________ Date of Inspection: _______ Type of Inspection: U Pre-rainy season U Monthly U Quarterly
U Annual U Re-inspection 1
Inspector(s): ___________________________________ Start Time:_____ End Time: ______
Defect
Trash and
Debris
1
Conditions When
Maintenance Is Needed
Maintenance
Needed? (Y/N)
Comments (Describe maintenance
Results Expected When Maintenance Is Performed
completed; and if any needed
maintenance was not conducted, note
what is needed and when it will be done)
Trash and debris cleared from site.
Trash and debris
accumulated on rock pad.
Visual evidence of
dumping.
Rock Pad
Native soil is visible
below rock pad.
Rock pad replaced to design standards.
Erosion
Soil erosion adjacent to rock
pad that exceeds 6 inches.
Visual evidence of water
discharging at concentrated
points.
Rock pad replaced to design standards or
redesigned to better control high flows.
Sediment
Discharge pipe is more
than 20% full of sediment
or debris.
Removal and proper disposal of sediment and debris.
Damaged
Pipes
Any part of the discharge
pipe is crushed or deformed
more than 20% or any other
failure of the piping.
Pipe repaired or replaced.
Re-inspection of a previously-noted maintenance issue.
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Inspection and Maintenance Checklist
Infiltration Swale/Bio-infiltration Basin (Bear Creek only)
Property Address: ________________________________________________Property Owner: ______________________________
Facility Name/Designator: ___________ Date of Inspection: _______ Type of Inspection: U Pre-rainy season U Monthly U Quarterly
U Annual U Re-inspection 1
Inspector(s): ___________________________________ Start Time:_____ End Time: ______
Defect
Trash
&
Debris
Contaminants
and Pollution
Vegetation
Conditions When
Maintenance Is Needed
Maintenance
Needed? (Y/N)
Comments (Describe maintenance
Trash and debris cleared from site.
Trash and debris
accumulated in basin
Visual evidence
of dumping
Any evidence of oil,
gasoline, contaminants
or other pollutants
Oil and contaminants removed and properly
disposed. No contaminants or pollutants present.
Vegetation mowed per specifications or
maintenance plan, so that flow is not impeded.
Vegetation should never be mowed lower than the
design flow depth. Remove clippings from the area
and dispose appropriately.
Integrated pest management of poisonous or noxious
vegetation, removing it manually by pulling by hand or
digging out weeds. Do not apply pesticides, herbicides,
or mossicides.
Planted vegetation
becomes excessively tall.
Presence of poisonous or
nuisance vegetation or
noxious weeds.
Tree/Brush
Growth and
Hazard Trees
Erosion
Results Expected When Maintenance Is Performed
completed; and if any needed
maintenance was not conducted, note
what is needed and when it will be done)
Growth does not allow
maintenance access or
interferes with
maintenance activity
Dead, diseased, or dying
trees
Trees do not hinder maintenance activities.
Remove hazard trees as approved by the City.
(Use a certified Arborist to determine health of
tree or removal requirements)
Eroded over 2 in. deep
where cause of damage is
still present or where there
is potential for continued
erosion.
Cause of erosion is managed appropriately. Areas
resoiled and/or remulched to fill in void areas.
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Infiltration Swale/Bio-infiltration Basin Inspection Checklist
Inspection Date: _________________
Property Address: _________________________________________________________________________ Facility Name/Designator: __________
Defect
Conditions When
Maintenance Is Needed
Maintenance
Needed? (Y/N)
Comments (Describe maintenance
Results Expected When Maintenance Is Performed
completed; and if any needed
maintenance was not conducted, note
what is needed and when it will be done)
Sediment
Accumulated sediment
affects inletting or
outletting condition of the
facility.
Sediment removed and area reseeded if necessary
to control erosion.
Damaged
Pipes
Any part of the piping that is
crushed or deformed more
than 20% or any other
failure to the piping.
Pipe repaired or replaced.
Mosquito
Vector
Breeding
Suitable habitats exist for
mosquito production (e.g.,
standing water for more
than 72 hours in areas
accessible to mosquitoes).
Water drainage rates are restored to design
standards. Standing water no longer exists or is
inaccessible to mosquitoes.
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Inspection and Maintenance Checklist
Catch Basins (Bear Creek & Franklin)
Property Address: ________________________________________________Property Owner: ______________________________
Facility Name/Designator ____________ Date of Inspection: _______ Type of Inspection: U Pre-rainy season U Monthly U Quarterly
U Annual U Re-inspection 1
Inspector(s): ___________________________________ Start Time:_____ End Time: ______
Defect
Conditions When
Maintenance Is Needed
Maintenance
Needed? (Y/N)
Comments (Describe maintenance
Results Expected When Maintenance Is Performed
completed; and if any needed
maintenance was not conducted, note
what is needed and when it will be done)
Debris and
Sediment
Accumulated debris or
sediment depth exceeds 12
inches or impedes flow from
inlet or outlet pipes.
All sediment and debris removed from storage area.
Runoff freely flows into and out of basin.
Damaged Pipes
Inlet or outlet piping
damaged or broken and
in need of repair.
Pipe repaired and/or replaced.
Joints Between
Basin/Pipe
Section
Structure
Contaminants
and Pollution
Cover
Any openings or voids
allowing material to be
transported into facility.
All joints between basin/pipe sections are sealed.
Cracks wider than 1/2-inch
and any evidence of soil
particles entering the
structure through the
cracks, or maintenance/
inspection personnel
determines that the vault is
not structurally sound.
Vault replaced or repaired to design specifications
and is structurally sound. No cracks more than 1/2inch wide at the joint of the inlet/outlet pipe.
Any evidence of oil,
gasoline, contaminants,
or pollutants.
Oil and contaminants removed and properly
disposed. No contaminants or pollutants present.
Cover is missing or only
partially in place.
Cover is difficult to remove
with normal lifting pressure.
Repair or replace cover. Manhole is closed
and can be removed and reinstalled by one
person to facilitate maintenance access.
1 Re-inspection of a previously-noted maintenance issue
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Sedimentation Manholes/Catch Basin Inspection Checklist
Inspection Date: ______________________
Property Address: _________________________________________________________________________ Facility Name/Designator: _________
Defect
Conditions When
Maintenance Is Needed
Ladder
Ladder is unsafe due to
missing rungs,
misalignment, not
securely attached to
structure wall, rust, or
cracks.
Mosquito
Vector
Breeding
Suitable habitats exist for
mosquito production (e.g.,
standing water in areas
accessible to mosquitoes)
[[== Insert Agency Name ==]]
Maintenance
Needed? (Y/N)
Comments (Describe maintenance
Results Expected When Maintenance Is Performed
completed; and if any needed
maintenance was not conducted, note
what is needed and when it will be done)
Ladder meets design standards. Allows safe
maintenance access.
Standing water no longer exists or is
inaccessible to mosquitoes.
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Drainage Area Maintenance
Property Address: ________________________________________________ Property Owner: _____________________________
__________ Date of Inspection: _______ Type of Inspection: U Pre-rainy season U Monthly U Quarterly
U Annual U Re-inspection 1
Inspector(s): __________________________________ Start Time:_____ End Time: ______
Facility Name/Designator:
Defect
Conditions When
Maintenance Is Needed
Maintenance
Needed? (Y/N)
Comments (Describe maintenance
Results Expected When Maintenance Is Performed
completed; and if any needed
maintenance was not conducted, note
what is needed and when it will be
done)
Snow on
Roads
Evidence of snow
Snow is plowed or magnesium chloride is used.
Ideally, no salt or gravel should be applied to road
along the stretches that drain to these facilities..
Moss on
roads or
sidewalks
Moss is present
Remove by hand or sweeping. Pressure washing can
cause turbid water by suspending soil particles; use
this method last. Never apply herbicides or
mossicides.
Landscapes
Weeds or moss
present
Integrated pest management of poisonous or noxious
vegetation, removing it manually by pulling by hand or
digging out weeds. Do not apply pesticides,
herbicides, or mossicides.
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Appendix D -- Monitoring Question 1 Monitoring Device
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Appendix E – Bibliography
Bureau of Environmental Services (BES). 2008. Portland Stormwater Management Manual. City of Portland,
Portland, OR. Accessed from http://www.portlandonline.com/bes/index.cfm?c=47952
Cahill, Maria, Derek Godwin and Marrisa Sowles (Cah). Infiltration Testing. Fact sheet. Oregon State University
Extension. Corvallis, OR: Oregon Sea Grant, 2011. Accessed from
http://extdev.cws.oregonstate.edu/drupal_stormwater/sites/default/files/Infiltration%20Testing.pdf
Cunningham, W.L., and Schalk, C.W., comps., 2011, Groundwater technical procedures of the U.S. Geological
Survey: U.S. Geological Survey Techniques and Methods 1–A1, 151 p.
(available only online at http://pubs.usgs.gov/tm/1a1/)
Grasslands Conservation Council of British Columbia (GCCBC), 2009. 6. Conducting Photo-Point Monitoring.
<http://www.bcgrasslands.org/monitoringmanual.htm>.
Oregon State University Extension Service, City of Bend. "Xeriscaping in the High Desert."
<http://extension.oregonstate.edu/deschutes/sites/default/files/xeri-all.pdf>.
Roundy, B.A. and J.L. Vernon. 1999. Watershed values and conditions associated with pinyon –juniper
communities. IN: Proceedings: Ecology and Management of Pinyon-Juniper Communities Within the
Interior West. USDA Forest Service Proceedings RMRS-9-9. 172-187.
Southeast Michigan Council Of Governments (SEMCOG). 2008. Low Impact Development Manual for
Michigan: A Design Guide for Implementers and Reviewers. Detroit, MI. Accessed from
http://library.semcog.org/InmagicGenie/DocumentFolder/LIDManualWeb.pdf
USDA Forest Service. Photo Point Monitoring. Fact Sheet. Salt Lake City, UT: Remote Sensing Applications
Center, n.d.
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