ALAMEDA COUNTY RESOURCE CONSERVATION DISTRICT
INITIAL STUDY AND DRAFT MITIGATED NEGATIVE DECLARATION
FOR
STONYBROOK CREEK FISH PASSAGE IMPROVEMENT PROJECT
February 4, 2014
Prepared by
Alameda County Resource Conservation District
3585 Greenville Rd, Suite 2
Livermore, CA 94550-6707
Contact: Leslie Koenig (925) 371-0154, ext. 115
This Report Has Been Prepared Pursuant to the
California Environmental Quality Act of 1970
State of California
TABLE OF CONTENTS
SECTION 1.0 PROJECT DESCRIPTION .............................................................................................. 3
INTRODUCTION – ENVIRONMENTAL COMPLIANCE.......................................................................................3
BACKGROUND .................................................................................................................................................3
PROJECT PURPOSE .........................................................................................................................................4
PROJECT TIMELINE ........................................................................................................................................4
SECTION 2.0 ENVIRONMENTAL CHECKLIST................................................................................. 5
DETERMINATION ............................................................................................................................................7
ENVIRONMENTAL IMPACTS .................................................................................................................9
I. AESTHETICS ..............................................................................................................................9
II. AGRICULTURE RESOURCES ............................................................................................... 10
III. AIR QUALITY ......................................................................................................................... 11
IV. BIOLOGICAL RESOURCES ................................................................................................. 12
V. CULTURAL RESOURCES ...................................................................................................... 19
VI. GEOLOGY AND SOILS .......................................................................................................... 20
VII. HAZARDS AND HAZARDOUS MATERIALS .................................................................... 22
VIII. HYDROLOGY AND WATER QUALITY ............................................................................ 24
IX. LAND USE PLANNING ........................................................................................................ 26
X. MINERAL RESOURCES ......................................................................................................... 26
XI. NOISE ...................................................................................................................................... 27
XII. POPULATION AND HOUSING ........................................................................................... 29
XIII. PUBLIC SERVICES ............................................................................................................ 30
XIV. RECREATION ...................................................................................................................... 31
XV. TRANSPORTATION/TRAFFIC ........................................................................................... 32
XVI. UTILITIES AND SERVICE SYSTEMS .............................................................................. 34
XVII. MANDATORY FINDINGS OF SIGNIFICANCE............................................................. 35
SECTION 3.0 REPORT PREPARATION ............................................................................................. 36
LEAD AGENCY .............................................................................................................................................. 36
PROJECT SPONSORS ..................................................................................................................................... 36
REFERENCES ................................................................................................................................................. 37
APPENDIX A
Figure 1: Project Location Map
Figure 2: Vicinity Map
Figure 3: Watershed Area Map
Figure 4: Project Plan Map – MP 8.60
Figure 5: Project Plan Map – MP 8.75
APPENDIX B
Natural Habitats, Species and Vegetation
APPENDIX C
Mitigation, Monitoring and Reporting Program (MMRP)
Page 2 of 37
SECTION 1.0 PROJECT DESCRIPTION
Introduction – Environmental Compliance
This Mitigated Negative Declaration (MND) has been prepared in accordance with the provisions of the
California Environmental Quality Act (CEQA) and its implementing guidelines. It assesses the potential
environmental impacts of the proposed Stonybrook Creek Fish Passage Improvement Project, located
along Stonybrook Creek, a tributary of the Alameda Creek along Palomares Road, in Alameda County,
California (Figure 1. Project Location Map). The Alameda County Resource Conservation District
(ACRCD) is the lead agency under CEQA for the proposed project.
This MND consists of an environmental checklist and a brief explanation of topics addressed in the
checklist. This proposed project consists of two culvert improvements that cross Stonybrook Creek along
the County of Alameda maintained Palomares Road at Mile Posts (MP) 8.60 and 8.75. It has been
determined that both culverts are barriers to all lifestages of anadromous fish, including federally listed
Distinct Population Segment (DPS) Central Coast California steelhead trout (Oncorhynchus mykiss).
These culvert improvements will allow fish (both anadromous and resident) to access an additional 0.7
miles of the creek upstream.
Background
Stonybrook Creek is a tributary to Alameda Creek, which drains into San Francisco Bay. The confluence
of the two creeks is located in Niles Canyon, approximately 13 river miles upstream from San Francisco
Bay (Figure 1: Project Location Map). The Stonybrook Creek watershed lies within Alameda County,
about 7 miles east of Hayward. Historically the watershed hydrology and channel function have been
impacted by low-density residential water use, minor agricultural development, and by the effects of
numerous road crossings over Stonybrook Creek. Approximately six square miles of central Alameda
County is drained by Stonybrook Creek. Elevations within the basin range from 160 feet at its mouth to
2,191 feet at its highest crest (MLA, 2010).
Efforts to restore runs of anadromous Central Coast California steelhead trout (Onchorhynchus mkiss) a
federally listed threatened species, are ongoing within the Alameda Creek Watershed, and most recently,
Stonybrook Creek. The lower 12 miles of Alameda Creek is a flood control channel with little viable
habitat for steelhead. Significant barriers preventing steelhead from reaching spawning and rearing habitat
are located within the upper section of the flood control channel and consist of concrete drop structure
and two inflatable rubber dams. The Alameda County Water District (ACWD) in association with the
Alameda Creek Fisheries Restoration Workgroup have scheduled to improve these fish barriers, including
addition of fish ladders on the BART weir, in 2013 to 2015, thus increasing the potential use of
Stonybrook Creek by migrating steelhead (ACWD, 2013).
As Stonybrook Creek is the first major tributary to Alameda Creek upstream from the flood control
channel, it provides viable upstream habitat for steelhead. Historically, this creek supported anadramous
fish species and in recent times a pair of Alameda Creek steelhead that were captured in the flood control
channel, radio-tagged, and released in Niles Canyon. These fish spawned in Stonybrook Creek, with the
offspring rearing in a nearby pool. In addition, resident rainbow trout are present and documented within
the creek (Becker, 2013).
With viable habitat evident along Stonybrook Creek, the primary purpose of this project is to improve
current fish barriers located along stream crossings. The barriers are located within the lower half of
Stonybrook Creek with a steep, boulder/cobble-type substrate. Stream crossings along County
Page 3 of 37
maintained Palomares Road (located at culvert mile-post (MP) 8.60 and 8.75) are under-sized, have
intercepted coarse sediment which would naturally have passed through the canyon and exited to
Alameda Creek creating a complete barrier for all lifestages of fish.
Addressing these barriers by two culvert improvements will progressively bring Stonybrook Creek closer
to restoration of its historic Central Coast California steelhead trout (Onchorhynchus mykiss) habitat,
opening 0.7 stream-miles of aquatic habitat upstream. Additional benefits of retrofitting and/or removing
stream barriers will be improved sediment management and reduced flood-related damages. Currently, a
concern for damage to public infrastructure and private property due to undersized crossings exists.
Project Purpose
This proposed project consists of two culvert improvements that cross Stonybrook Creek along the
County of Alameda maintained Palomares Road at Mile Posts (MP) 8.60 and 8.75. It has been determined
that both culverts are barriers to all lifestages of anadromous fish, including federally listed Distinct
Population Segment (DPS) Central Coast California steelhead trout (Oncorhynchus mykiss).
The primary concerns that led the sponsor, the Alameda County Resource Conservation District
(ACRCD), to propose the Stonybrook Creek project are: a) presence of barriers to migration of
anadromous Central Coast California steelhead and resident rainbow trout to identified spawning and
rearing habitat in Stonybrook canyon and b) a concern for damage to public infrastructure and private
property due to undersized crossings.
The proposed project is funded by a federal appropriation from Congressman Fortney Pete Stark (Public
Law 111-80 (Section 729) and Conference Report 111-279, Title II) that is directed through the Natural
Resources Conservation Service (NRCS) to the Alameda Creek Watershed through the PL 83-566
Program. Additional funding is being provided by a grant through the Environmental Protection Agency’s
San Francisco Bay Water Quality Improvement Fund. The project is being implemented jointly with the
ACRCD and NRCS.
Project Timeline
Construction activities related to this project are scheduled to begin in August 2014 and will last
approximately six to eight weeks. Associated vegetative plantings for this project is scheduled to occur
between December 2014 – January 2015. All equipment work for the Stonybrook Creek project will
occur before October 15th, 2014 - stream work thereafter is not permitted without approval from the
appropriate regulatory permits. Work is anticipated to occur between the hours of 7am-7pm, MondayFriday with the possibility of Saturday construction if necessary.
Project Equipment/Delivery
Equipment used during construction phases of this project inclues: bulldozers, loaders, cranes, and dump
trucks. The equipment will be staged in the eastbound lane of Palomares Road between MP 8.60 and MP
8.75. To access the project site, the equipment will use the northeastern bank of the creek from the
existing roadway pullout. Temporary regrading, footing installation and removal of vegetation will be
required for construction of a temporary stream crossing at MP 8.60 and for temporary equipment access.
After the completion of construction for this project, all temporary disturbance due to the project will be
restored.
Page 4 of 37
SECTION 2.0 ENVIRONMENTAL CHECKLIST
1.
Project title: Stonybrook Creek Fish Passage Improvement Project
2.
Lead agency name and address: Alameda County Resource Conservation District,
3585 Greenville Road, Suite #2, Livermore, CA 94550
3.
Contact person and phone number: Leslie Koenig, (925) 371-0154, ext. 115
4.
Project location: 320 linear feet of Stonybrook Creek (160 linear feet at MP 8.60, 160 linear feet
at MP 8.75), Parcel No: 085A00000100 & 085A500000204, Alameda County
5.
Project sponsor's name and address:
Alameda County Resource Conservation District and the Natural Resources Conservation
Service; 3585 Greenville Road, Suite #2, Livermore, CA 94550
6.
General plan designation: Agricultural
7.
Zoning:“A” – Agricultural
8.
Description of project:
The Stonybrook Creek Fish Passage Improvement Project consists of two culvert improvements
that cross Stonybrook Creek along Palomares Road at Mile Posts (MP) 8.60 and 8.75. The road
and the culverts are operated by Alameda County Public Works Department. Additional work
will occur within the stream on privately owned lands. It has been determined that both culverts
are barriers to all lifestages of anadromous fish, including federally listed Distinct Population
Segment (DPS) Central Coast California steelhead trout (Oncorhynchus mykiss). These culvert
improvements will allow fish (both anadromous and resident) to access an additional 0.7 miles of
the creek upstream. The project will be installed according to NRCS standards and
specifications.
Culvert Improvements
The project will include a full replacement of the culvert at MP 8.60 and a culvert retrofit at MP
8.75. See Appendix A (Figure 4: Project Plan Map – 8.60 and Figure 5: Project Plan Map – 8.75)
for the Construction Drawing 50% Design Details. The crossings are spaced 800 feet apart and
the overall channel slope between them is 9.0 percent (MLA, 2013).
Mile Post 8.60 Culvert Barrier
The culvert crossing at MP 8.60 is located approximately 6,400 feet (1.21 miles) upstream of the
Stonybrook Creek confluence with Alameda Creek (MLA, 2013). The existing crossing consists
of a grouted masonry channel 31 feet in length and a concrete bridge deck in good condition. The
masonry channel under the bridge was constructed in 1938 and has since been grouted. It has a
trapezoidal shape with a bottom width of approximately 9.0 feet and bottom slope of 3.9 percent
(MLA, 2013).
Currently the culvert crossing at MP 8.60 is perched several feet above an outlet pool, which
creates a full barrier to adult steelhead and adult rainbow trout at all flows. The barrier is created
due to a combination of the height of the outlet drop with shallow water depths and high
velocities associated with the relatively steep slope of the culvert. The outlet drop appears to vary
from year to year and was 4.8 feet during a 2005 investigation (MLA, 2013). In addition to the
barrier, this culvert has a low point on the roadway adjacent to the crossing that allows flow to
overtop the road during storm events before the headwater reaches the bottom of the bridge deck,
Page 5 of 37
with return periods of less than 25 years. Overflow from the undersized culvert has caused
erosion along the road and streambank downstream.
The design at the upstream crossing includes: removal of the existing concrete and masonry
culvert while providing temporary traffic access, re-grading of the channel in the vicinity of the
crossing, with the placement of a new pre-cast concrete arch culvert and wing walls on cast-inplace strip footings, and the paving of the final roadway over the new culvert (MLA, 2005a & b)
(Figure 4: Project Plan Map – 8.60).
Mile Post 8.75 Culvert Barrier
The culvert crossing at MP 8.75 is located approximately 5,500 feet (1.04 miles) upstream of the
Stonybrook Creek confluence with Alameda Creek (MLA, 2013). The crossing is a reinforced
concrete box that is 8 feet wide and 9 feet tall. The culvert is 89.4 feet in length, including the
inlet and outlet aprons, and has an overall slope of 7.3 percent. The crossing contains a large fill
prism and the roadway is over 25 feet above the culvert invert (Figure 5 – Project Plan Map –
8.75).
The culvert outlet is at grade with the downstream scour pool, allowing fish to swim into the
culvert. However, the shape of the culvert floor and its steep slope produces insufficient water
depths and excessive water velocities for passage of adult steelhead and adult rainbow trout
during all fish passage flows. The culvert is also undersized for the stream channel, becoming
submerged during storms with a return period of approximately 5 years. The presence of the
culvert has caused a pile of large boulders to deposit immediately upstream of the culvert inlet,
creating an additional fish migration barrier with a 5.5 foot vertical drop that is impassable to
adult steelhead and adult rainbow trout. This vertical drop is higher than the natural drops over
bedrock or boulders that have been observed in the creek and is the only known boulder passage
barrier on Stonybrook Creek.
The proposed plan for the crossing at MP 8.75 includes installation of angled baffles throughout
the box culvert and re-grading the upstream channel to eliminate the severe boulder jam in front
of the culvert inlet. The baffle design optimizes fish passage conditions while avoiding a
reduction in culvert capacity.
9.
Surrounding land uses and setting:
Stonybrook Creek is a tributary to Alameda Creek, which drains into San Francisco Bay (Figure
1: Project Location Map, Figure 2: Vicinity Map and Figure 3: Watershed Area Map). The
confluence of the two creeks is located in Niles Canyon, approximately 13 river miles upstream
from San Francisco Bay. The Stonybrook Creek Watershed lies within Alameda County, about 7
miles east of Hayward. Historically the watershed hydrology and channel function have been
impacted by low-density residential water use, minor agricultural development, and by the effects
of numerous road crossings over Stonybrook Creek. Approximately six square miles of central
Alameda County is drained by Stonybrook Creek. Elevations within the basin range from 160
feet at its mouth to 2,191 feet at its highest crest (MLA, 2010).
The culvert improvements are located off of Palomares Road, which is operated by the Alameda
County Public Works Department, adjacent to private lands. Palomares Road runs parallel to
Stonybrook Creek between State Route 84 (Niles Canyon Road) south of the site and the City of
Castro Valley and Highway 580 to the north. The canyon portion of Stonybrook Creek has few
residences due to large parcel sizes and steep topography.
Page 6 of 37
Land use along Palomares Road north of the site includes residential development, small
vineyards and other rural land uses (e.g. horse boarding facilities and a religious institution).
Land use south of the proposed action site includes residential development. The adjacent ridges
to the west and east of the site are both grazed rangeland. Sunol Ridge west of the proposed
project site is part of East Bay Regional Park District’s Pleasanton Ridge Regional Park, which
currently includes over 5,000 acres of forest and grassland preserved for habitat, grazing and
recreation.
10.
Other public agencies whose approval is required (e.g., permits, financing approval, or
participation agreement.).




U.S. Army Corps of Engineers Section 404 permit
California Department of Fish and
Wildlife - Lake and Streambed
Alteration Agreement (1602)
San Francisco Bay Regional Water
Control Board – 401 Water Quality
Certification
National Environmental Policy Act
(NEPA), Environment Assessment


State Historic Preservation Office –
Section 106 of the National Historic
Preservation Act (NRCS is the
responsible agency)
U.S. Fish and Wildlife Service –
Biological Opinion through U.S.
Army Corps of Engineers Section 7
Nexus
Environmental Factors Potentially Affected
The environmental factors checked below would be potentially affected by this project, involving at least
one impact that is a "Potentially Significant Impact" as indicated by the checklist on the following pages.
X
Aesthetics
Agriculture Resources
Air Quality
Biological Resources
Cultural Resources
Geology /Soils
Hazards & Hazardous
Materials
Hydrology / Water
Quality
Land Use / Planning
Mineral Resources
Noise
Population / Housing
Public Services
Recreation
Transportation/Traffic
Utilities / Service Systems
Mandatory Findings of Significance
Determination
(To be completed by the Lead Agency) On the basis of this initial evaluation:
I find that the proposed project COULD NOT have a significant effect on the environment, and
a NEGATIVE DECLARATION will be prepared.
X
I find that although the proposed project could have a significant effect on the environment,
there will not be a significant effect in this case because revisions in the project have been
made by or agreed to by the project proponent. A MITIGATED NEGATIVE
DECLARATION will be prepared.
Page 7 of 37
I find that the proposed project MAY have a significant effect on the environment, and an
ENVIRONMENTAL IMPACT REPORT is required.
I find that the proposed project MAY have a "potentially significant impact" or "potentially
significant unless mitigated" impact on the environment, but at least one effect 1) has been
adequately analyzed in an earlier document pursuant to applicable legal standards, and 2) has
been addressed by mitigation measures based on the earlier analysis as described on attached
sheets. An ENVIRONMENTAL IMPACT REPORT is required, but it must analyze only the
effects that remain to be addressed.
I find that although the proposed project could have a significant effect on the environment,
because all potentially significant effects (a) have been analyzed adequately in an earlier EIR
or NEGATIVE DECLARATION pursuant to applicable standards, and (b) have been avoided
or mitigated pursuant to that earlier EIR or NEGATIVE DECLARATION, including revisions
or mitigation measures that are imposed upon the proposed project, nothing further is required.
Signature
Printed Name
Date
James Perry, President, Board of Directors
Page 8 of 37
ENVIRONMENTAL IMPACTS
I. AESTHETICS
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No Impact
Would the project
a) Have a substantial adverse effect on a scenic
vista?
x
b) Substantially damage scenic resources,
including, but not limited to, trees, rock
outcroppings, and historic buildings within a
state scenic highway?
x
c) Substantially degrade the existing visual
character or quality of the site and its
surroundings?
x
d) Create a new source of substantial light or
glare which would adversely affect day or
nighttime views in the area?
x
Environmental Setting
The proposed project is located across two stream crossings (MP 8.60 and MP 8.75) in Stonybrook Creek
in Stonybrook Canyon. Stonybrook Creek is a tributary to Alameda Creek, which drains into San
Francisco Bay. The confluence of which is located in Niles Canyon, approximately 13 river miles
upstream from San Francisco Bay. The Stonybrook Creek Watershed lies within Alameda County, about
7 miles east of Hayward. Historically the watershed hydrology and function have been impacted by lowdensity residential water use, minor agricultural development, and by the effects of numerous road
crossings over Stonybrook Creek. Approximately six square miles of central Alameda County is drained
by Stonybrook Creek. Elevations within the basin range from 160 feet at its mouth to 2,191 feet at its
highest crest (MLA, 2010).
Discussion of Aesthetics: Short-term impacts on the scenic vista and visual character of project site will
occur during construction due to removal of existing concrete, modifications of culverts, and the
installation of a temporary bridge. Short-term impacts to will be immediately mitigated by the planting of
native vegetation. Long-term impacts include complete removal of the existing historic masonry culvert
with overlying concrete bridge at MP 8.60 and modifications to the box culvert at MP 8.75. All
modifications (complete culvert removal and retrofit) will result in a visually changed landscape.
However, culvert improvments at MP 8.60 and MP 8.75 will mitigate for the aesthetic loss of existing
culvert structures. Thus, when completed, the restoration project will result in long-term, improved area
aesthetics with culvert improvements.
Finding: No Impact
Page 9 of 37
II. AGRICULTURAL RESOURCES
Potentially
Significant
Impact
Less Than
Less Than
No Impact
Significant
Significant
with
Impact
Mitigation
Incorporation
In determining whether impacts to agricultural resources are significant environmental effects, lead agencies may
refer to the California Agricultural Land Evaluation and Site Assessment Model (1997) prepared by the California
Dept. of Conservation as an optional model to use in assessing impacts on agriculture and farmland. Would the
project:
a) Convert Prime Farmland, Unique Farmland, or
Farmland of Statewide Importance (Farmland),
as shown on the maps prepared pursuant to the
Farmland Mapping and Monitoring Program of
the California Resources Agency, to nonagricultural use?
x
b) Conflict with existing zoning for agricultural
use, or a Williamson Act contract?
x
c) Involve other changes in the existing
environment which, due to their location or
nature, could result in conversion of Farmland, to
non-agricultural use?
x
Discussion of Agricultural Resources: The project is located in a rural unicorporated area, with adjacent
ridges to the west and east of the site as grazed rangelend. North of the project site small vineyards mixed
with other rural land uses are present. No special-status farmland is present within the immediate vicinity
of the project area. The proposed project will not affect or conflict with existing zoning or contracts.
Thus, the project will not result in a negative impact to the agricultural land.
Finding: No Impact.
Page 10 of 37
III. AIR QUALITY
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No Impact
Where available, the significance criteria established by the applicable air quality management or air pollution
control district may be relied upon to make the following determinations. Would the project:
a) Conflict with or obstruct implementation of
the applicable air quality plan?
x
b) Violate any air quality standard or contribute
substantially to an existing or projected air
quality violation?
x
c) Result in a cumulatively considerable net
increase of any criteria pollutant for which the
project region is non-attainment under an
applicable federal or state ambient air quality
standard (including releasing emissions which
exceed quantitative thresholds for ozone
precursors)?
x
d) Expose sensitive receptors to substantial
pollutant concentrations?
x
e) Create objectionable odors affecting a
substantial number of people?
x
Discussion of Air Quality: The project is expected to create short-term effects (up to 8 weeks) on air
quality in the form of increased dust, particulate matter and exhaust odors caused by construction activity.
These effects are local in nature and would end with completion of the project. The proposed project will
not affect or conflict with implementation of air quality plans. The proposed project will not violate any
air quality standards nor contribute substantially to air quality violations. As results of this proposed
project, the region will not see a considerable increase of air pollutants for the region. Additionally, the
proposed project will not expose sensitive receptors to substantial pollutant concentrations, nor will the
proposed project create objectionable odors affecting substaintial numbers of people.
Finding: Less than significant with employment of control measures to control dust.
Page 11 of 37
IV. BIOLOGICAL RESOURCES
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No Impact
Would the project
a) Have a substantial adverse effect, either
directly or through habitat modifications, on any
species identified as a candidate, sensitive, or
special status species in local or regional plans,
policies, or regulations, or by the California
Department of Fish and Game or U.S. Fish and
Wildlife Service?
x
b) Have a substantial adverse effect on any
riparian habitat or other sensitive natural
community identified in local or regional plans,
policies, regulations or by the California
Department of Fish and Wildlife or US Fish and
Wildlife Service?
x
c) Have a substantial adverse effect on federally
protected wetlands as defined by Section 404 of
the Clean Water Act (including, but not limited
to, marsh, vernal pool, coastal, etc.) through
direct removal, filling, hydrological interruption,
or other means?
x
d) Interfere substantially with the movement of
any native resident or migratory fish or wildlife
species or with established native resident or
migratory wildlife corridors, or impede the use of
native wildlife nursery sites?
x
e) Conflict with any local policies or ordinances
protecting biological resources, such as a tree
preservation policy or ordinance?
x
f) Conflict with the provisions of an adopted
Habitat Conservation Plan, Natural Community
Conservation Plan, or other approved local,
regional, or state habitat conservation plan?
x
Environmental Setting
Natural habitats found within the Stonybrook Creek include Annual Grassland, Coastal Oak Woodland,
Montane Riparian, Valley Foothill Riparian, Riverine Aquatic Habitat and Fresh Emergent Wetland. Full
descriptions of habitats and vegetation communities can be found in Appendix B: Natural Habitats,
Species and Vegetation. Summarized details of the vegetation and wildlife found within the proposed
action vicinity are included below.
Page 12 of 37
Vegetation
Naturally occurring riparian forest and scrub occurs in and along the margins of the active channels on
intermittent and perennial streams. The existing vegetation at the proposed action site varies with
elevation and distance from the stream channel and includes: Coast live oak (Quercus agrifolia), valley
oak (Quercus lobata), western sycamore (Platanus racemosa), California bay (Umbellularia californica),
bigleaf maple (Acer macrophyllum), Pacific madrone (Arbutus menziesii) and scattered willows (Salix
spp.) along the streambanks. Several non-native Parney’s contoneaster (Contoneaster lacteus), and plum
(Maloideae prunus) are found along the upper floodplain. The understory of the upper banks and terraces
are dominated by annual grasses and annual forbs. Shrub species such as California sage (Artemisia
californica), poison oak (Toxicodendron diversilobum), and coyote brush (Baccharis pilularis) are also
present.
Vegetation Impacts
Short term effects of the proposed action include the loss of native trees and cover due to the need to
remove or trim trees in order to install practices. A total of nine trees will require removal as a result of
project impacts: five trees from MP. 8.60 and four trees at MP 8.75. Impacts to existing vegetation will be
fully mitigated through replacement and enhancement planting. Details on the trees that will be removed
are below in Table 1.
Long term impacts of the propsed project include an increase in trees and tree canopy due to tree
replacement mitigation rate of 3:1 for trees lost less than 4 inches in diameter at breast height (dbh) and
9:1 for trees greater than 4:1 dbh. See Mitigation Measure 2 in the Mitigation, Monitoring and Reporting
Plan (MMRP) included in Appendix C.
Table 1. On-Site Tree Removal Impacts
# of Plants
Greater than
Species
4" DBH1
Non-natives
Parney's cotoneaster
1
Natives
1
2
Total Plants in
Survey Area
Proposed
Mitigation Ratio
1
1:12
California bay laurel
2
2
9:1
Big leaf maple
2
2
9:1
White alder
2
2
9:1
Coast live oak
2
2
3:1
Trees of a size less than 4” diameter at breast height (DBH) do not require mitigation.
Non-natives will be replaced with an appropriate native species.
The vegetation will be installed in the winter 2014-2015. Following installation plantings will be
monitored and maintained for the required monitoring period as defined by the final permits.
Replacement planting will be conducted as needed to establish sufficient vegetation and meet success
criteria at the site. The stream channel through the proposed project site is highly shaded and lacks
emergent aquatic vegetation that would normally be found in wetland areas. Impacts to existing
vegetation will be fully mitigated through replacement and enhancement plantings. This project will
enhance fish habitat and riparian habitat for plant and wildlife species.
Wildlife
Within a 5 mile radius surrounding the Stonybrook Creek proposed action site, the California Natural
Diversity Database (CNDDB) reports the presence of five federally listed threatened or endangered
species of plants and animals and 12 additional species of concern to the California Department of Fish
Page 13 of 37
and Wildlife (CDFW). See Appendix B: Natural Habitats, Species and Vegetation for the descriptions of
all federal and state listed species identified by CDNNB (2013) potentially present within five miles of
the proposed action. Below are selected species descriptions for threatened and endangered species and
the species of special concern that have moderate to high potential to occur at the proposed action site.
California Red-Legged Frog (Rana draytonii) – Federal Threatened Species; State Species of Special
Concern (USFWS, 2007a)
The California red-legged frog occupies a distinct habitat where breeding adults are commonly found in
dense, shrubby or emergent riparian vegetation closely associated with deep (greater than 2 feet) still or
slow moving water. The largest densities of California red-legged frogs are associated with deep-water
pools such as livestock ponds, with dense stands of cattails, tules, or willows. Tadpoles and metamorphs
(a transitional lifestage between the tadpole and frog) can been found in a variety of aquatic habitats,
including streams, deep pools, backwaters within streams and creeks, ponds, marshes, and lagoons.
Stonybrook Creek and the proposed action site are not located within a Critical Habitat recovery area for
the California red-legged frog. However the proposed action site is considered acceptable habitat. The
steep banks, rocky and embedded cobble creek, and still-water pools present potential habitat for the
California red-legged frog. California Department of Fish and Wildlife (CNDDB, 2013) records indicate
the presence of California red-legged frogs within a 5 mile radius (approximately 1.65 miles southeast),
downstream along Alameda Creek and adult frogs have been observed upstream of the proposed action
during stream surveys conducted in 2013.
The proposed action area currently provides dispersal and refugia habitat for CA red-legged frogs. The
breeding habitat value and quality is uncertain. Stream surveys conducted in June and July 2013
discovered the presence of adult red-legged frogs. No tadpoles were observed during these surveys and it
would be anticipated to find them during the survey period if there was successful breeding. The
presence of the stillwater pools within the creek may provide the appropriate breeding habitat for the
California red-legged frog. Stonybrook Creek is a steep, well shaded canyon and it is unknown if there is
enough sunlight to provide suitable breeding. The removal of the outlet pool at MP 8.60 to regrade and
improve passage for steelhead may have a negative effect on California red-legged frog dispersal, refugia
and potential breeding habitat. The proposed action plan includes creation of 7 step pools, totalling 1,120
cubic feet of water, as part of the proposed action, with the intention of replacing the same pool volume
lost. Impacts to the loss of the outlet pool volume will be fully mitigated through the replacement steppool morphology. The potential impacts to the California red-legged frog will require consultation with
the United States Fish and Wildlife Service. A biological assessment will be completed and appropriate
avoidance and minimization measures during construction will be identified.
Central Coast California Steelhead (Oncorhynchus mykiss) – Federal Threatened Species (Jones and
Stokes, 2006)
The primary habitat for Central Coast California Distinct Population Segment (DPS) steelhead consists of
shaded pools of small, cool, low-flowing stream reaches. They can use warm water habitats below some
dams or pipeline outfalls, where summer releases provide high summer flows and fast-water feeding
habitat. Adult steelhead require spawning sites with gravel substrate with sufficient flow velocity to
maintain circulation through the gravel. Juveniles need deeper waters where low velocity areas are in
close proximity to higher velocity areas and cover is provided by boulders, undercut banks, logs, or other
objects.
California Department of Fish and Wildlife (CNDDB, 2013) records indicate the presence of these
species within a 5 mile radius downstream in Alameda Creek. CNDDB records include extant population
Page 14 of 37
records for anadromous steelhead within Stonybrook Creek. Steelhead from Alameda Creek have been
identified as genetically associated with the Central California Coast stock listed as a federally threatened
species. This listing has focused public attention on restoring fish passage on Alameda Creek and its
tributaries. Naturally sustaining populations of steelhead are currently not present in Stonybrook Creek.
However, once barriers in Alameda Creek and Stonybrook Creek are removed, the entire Stonybrook
Creek and the proposed action site potentially provide ideal habitat for steelhead and resident rainbow
trout, as Alameda Creek and its tributaries (Stonybrook Creek included) historically contained steelhead.
Aside from two adult steelhead who were transported over the BART weir (an impassable fish barrier
downstream) in Fremont in February 25, 2008 (Alexander et al. 2008), no anadromous steelhead have
been reported in Stonybrook Creek since the 1960s (CNDDB, 2013).
Resident non-anadromous Oncorhynchus mykiss (rainbow trout) have been observed throughout the
lower portion of Stonybrook Creek below the proposed action sites in all study years – 1999, 2002, 2006,
2008, and 2012 (da Costa, 2002; Alexander et al., 2006 and 2008; MLA, 2001 and 2010, Becker; 2013).
The current Oncorhynchus mykiss population appears to be self-sustaining and available habitat within
the lower canyon reaches provides sufficient pool rearing and spawning habitat (Becker, 2013).
Stonybrook Creek provides potential spawning habitat and rearing habitat for juvenile steelhead during
spring migration through late summer and fall (Becker, 2013). Downstream removal of fish barriers
(addition of fish ladders on the BART weir) by the Alameda County Water District in association with the
Alameda Creek Fisheries Restoration Workgroup are planned for 2013 to 2015, increasing the potential
use of the Stonybrook Creek by migrating steelhead (ACWD, 2013).
Long term, the proposed project has the potential to positively impact the federally threatened Central
Coast California steelhead (Oncorhynchus mykiss) once the downstream barriers in Alameda Creek are
made passable. The entire portion of Stonybrook Creek is considered habitat for steelhead by the
California Department of Fish and Wildlife (CNDDB, 2013). The proposed action will result in access to
an additional 0.7 miles of stream habitat valuable to resident rainbow trout and potentially steelhead for
both spawning and rearing. The newly accessible reach includes at least one large pool that will likely
provide over-summer rearing habitat. Becker (2013) estimates that the removals would increase the
available over-summering pool volume in the canyon by 45 to-55 percent. Therefore, NRCS anticipates
that the net effect of the action on salmonid habitat is positive.
Federal Consultation of Wildlife Impacts
Section 7 of the Endangered Species Act requires federal agencies to consult with the U.S. Fish and
Wildlife Service (USFWS) if a proposed action will affect endangered or threatened species. The project
will require a permit from the U.S. Army Corps of Engineers (ACOE) under Section 404 of the Clean
Water Act. In 1999, the USFWS prepared a programmatic Biological Opinion (“Programmatic Formal
Endangered Species Act Consultation on Authorization under the Nationwide Permit Program for
Projects that May Affect the California red-legged frog”), allowing the ACOE to approve projects that
result in only minimal impacts if they meet certain conditions. This project is anticipated to append to
that Programmatic Biological Opinion to address that the project may affect the California red-legged
frog.
It is anticipated that the stream will be dry during construction. However, if isoloated pools or intermittent
flows persist into the construction season due to a wetter than normal winter, dewatering measures will be
undertaken to minimize impacts on water quality and wildlife.
The following mitigation measures will be implemented to address potential impacts on biological
resources. Actions to implement and monitor these measures is included in the MMRP in Appendix C.
Page 15 of 37
Mitigation No.
Mitigation Measure
1
Construction Hours.
Ground disturbing activities shall occur only during daylight hours.
2
Vegetation Disturbance.
Vegetation disturbance will be limited to the trees identified in the project plan. All impacts to
trees will be mitigated through replanting of in-kind native plant species. The tree replacement
mitigation rate of 3:1 for trees lost less than 4 inches in diameter at breast height (dbh) and 9:1
for trees greater than 4:1 dbh
3
No Plastic mono-filament matting.
No plastic mono-filament erosion control matting shall be used for erosion control.
4
Sediment Removal.
Sediment removed during the stream restoration activities will not be placed where it can enter
into waters of the state as per Fish and Game Code 5650.
5
Capping structures.
All construction pipes, culverts, or similar structures that are stored in the project area for one or
more overnight periods shall be securely capped prior to storage or thoroughly inspected for
animals if the pipe is subsequently buried, capped, or otherwise used or moved in any way.
6
Escape Ramps.
All steep-walled trenches and/or holes deeper than 6-inches shall be covered at night or an
escape ramp shall be placed in them to facilitate escape by any wildlife that may fall into the
excavated area. The ramp may be constructed of either dirt fill or wood planking or other
suitable material that is placed at an angle of no greater than 30 degrees. Trenches and holes
shall be checked every morning prior to construction activity. If a listed species is present in the
trench or hole, a qualified biologist shall be notified immediately and no construction activity
shall take place within 100 feet of the site until the animal is relocated.
7
Cavity/Tree Nesting/Breeding Bird Surveys.
No more than two weeks prior to the initiation of tree removals or pruning, grading or other
construction activities scheduled during the nesting/breeding season of protected raptors and
migratory birds (February 15 to August 30) a survey will be conducted by a qualified biologist
for nesting bird activity. If nesting birds are found within the area, a 50 foot buffer from
passerines and 300 foot buffer from raptors will be implemented unless another buffer is
authorized by the US Fish and Wildlife Service and/or the Department of Fish and Wildlife.
8
Bat Surveys.
Trimming or removal of trees is required within the project area. No more than 30 days before
removal, all trees subject to the impact will be surveyed for potential roost habitat (cavities,
crevices) by a qualified biologist. If roosting bats are identified, tree/limb removal must occur
during March 1 to April 15 or August 15 to October 15 unless otherwise authorized by the US
Fish and Wildlife Service and/or the Department of Fish and Wildlife.
9
Equipment Staging and Storage.
Staging and storage areas for equipment, materials, fuels, lubricants and solvents, shall be
located outside of the stream channel. Stationary equipment such as motors, pumps, generators,
compressors and welders, located within or adjacent to the stream shall be positioned over drip
pans. Any equipment or vehicles driven and/or operated within or adjacent to the stream must
be checked and maintained daily, to prevent leaks of materials that if introduced to water could
be deleterious to aquatic life. Vehicles must be moved away from the stream prior to refueling
and lubrication. The use or storage of petroleum-powered equipment shall be accomplished in a
manner to prevent the release of petroleum materials into waters of the state in accordance with
Fish and Game Code 5650.
Page 16 of 37
Mitigation No.
Mitigation Measure
10
Dewatering Activities.
If dewatering activities are required, water will be diverted by installation of a temporary
barrier. All water above the barrier will be diverted downstream at an appropriate rate to
maintain downstream flows during construction. A qualified biologist, with all necessary State
permits shall relocate fish, amphibians and other native aquatic species within the project site.
All reasonable efforts shall be made to capture and move all stranded aquatic life observed in
the dewatered areas. Adequate water depth and channel width will be maintained at all times to
allow for fish passage. When construction is completed, the barriers to flow will be removed in
a manner that will allow flow to resume with the least disturbance possible to the substrate.
11
Use of Herbicides.
Use of herbicides to address non-native plant species will occur according to labeled directions
and local, State, and Federal regulations and guidelines. Activities shall be limited to the dry
period of the year and shall be restricted to periods of low rainfall (less than ¼” per 24 hour
period), time periods with less than a 30% chance of rain, or dry weather periods. If rain is
predicted based on the above criteria, within 72 hours during project activity, all activities shall
cease until no further rain is forecast.
Implement Avoidance and Minimization Measures for Potential Impacts to California redlegged frog and other amphibian species
a. Restoration activities s will take place between August 31-October 31 (or the first rainfall of
the season depositing more than 0.25 inch).
b. A qualified biologist shall survey the work site immediately prior to construction activities.
If red-legged frogs adults, larvae, or eggs are found, the qualified biologist will determine if
moving any of these life-stages is appropriate. In making this determination the qualifed
biologist shall consider if an appropriate relocation site exists. The qualifed biologist shall be
allowed sufficient time to move red-legged frogsfrom the work site before work activities begin.
c. Bare hands shall be used to capture red-legged frogs. Qualified biologists will not use soaps,
oils, creams, lotions, repellents, or solvents of any sort on their hands within two hours before
and during periods when they are capturing and relocating individuals. To avoid transferring
disease or pathogens of handling of the amphibians, qualified biologists will follow the
Declining Amphibian Populations Task Force’s “Code of Practice.”
12
d. Only qualified biologists will capture, handle, and relocate red-legged frogs.
e. A qualified biologist shall be present on site during all grading, dewatering, tree removal, instream construction activities, and relocation of red-legged frogs. After instruction of project
personnel, relocation of red-legged frogs, and the activities listed above have been completed,
the qualified biologist shall designate a person to monitor on-site compliance. The qualified
biologist shall ensure that this individual receives the appropriate training and is competent in
the identification of red-legged frogs.
f. To address the removal of the outlet pool at MP 8.60 to regrade and improve passage for
steelhead the proposed action plan includes creation of 7 step pools, totalling 1,120 cubic feet of
water. Impacts to the loss of the outlet pool volume will be fully mitigated through the
replacement step-pool morphology. The potential impacts to the California red-legged frog will
require consultation with the United States Fish and Wildlife Service. A biological assessment
will be completed and appropriate avoidance and minimization measures during construction
will be identified.
Page 17 of 37
Mitigation No.
13
Mitigation Measure
Implement Avoidance and Minimization Measures for Potential Impacts to Alameda
whipsnake and other snakes.
a. No plastic mono-filament erosion control matting will be used for erosion control
b. Disturbance shall only take place between June 15- October 31, when the whipsnake is more
active and less likely to be impacted.
14
Implement Avoidance and Minimization Measures for Potential Impacts to the San
Francisco Dusky Footed Woodrat.
Preconstruction surveys will be conducted by a qualified biologist for projects that occur within
woodrat habitat for the presence of middens. If middens are found within the breeding season
(December 1 to August 31) exclusion fence will be installed to protect the middens from
construction activities.
Finding: Less than significant impact with implementation of mitigation and avoidance and minimization
measures.
Page 18 of 37
V. CULTURAL RESOURCES
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No Impact
Would the project:
a) Cause a substantial adverse change in the
significance of a historical resource as defined in
'15064.5?
x
b) Cause a substantial adverse change in the
significance of an archaeological resource
pursuant to '15064.5?
x
c) Directly or indirectly destroy a unique
paleontological resource or site or unique
geologic feature?
x
d) Disturb any human remains, including those
interred outside of formal cemeteries?
x
Discussion of Cultural Resources: “Cultural resources” is a broad term that refers to prehistoric and
historic-era archaeological sites, objects, and features, aspects of the built environment, and sacred sites
and other traditional cultural properties. The project includes ground-disturbing activities that could
affect cultural resources if they are present. The Natural Resources Conservation Service (NRCS) as the
lead federal agency on this project is responsible for compliance with cultural resource protection
requirements.
The National Historic Preservation Act (NHPA) of 1966, as amended, is the primary legislation outlining
the federal government’s responsibilities regarding cultural resources. Specifically, Section 106 of the
NHPA requires federal agencies to take into account the effects of their undertakings on cultural
resources included in, or eligible for inclusion in, the National Register of Historic Places (National
Register) through a process outlined at 36 CFR Part 800. Following the Section 106 process, NRCS
identified the masonry culvert with overlying concrete bridge at MP 8.60 and the box culvert at MP 8.75
as the only cultural resources of concern within the area of potential effects. Based on information
obtained through background research and on-the-ground survey, both structures were evaluated using the
National Register criteria (36 CFR Part 63) and determined to be not eligible for National Register
inclusion. Pursuant to 36 CFR § 800.4(d)(1), NRCS has reached a finding of no historic properties
affected for the proposed undertaking. Impacts to cultural resources resulting from the proposed project
are considered to be less than significant.
As required by 36 CFR Part 800, NRCS is consulting with the State Historic Preservation Officer
(SHPO), seeking consensus on the determinations of eligibility for the two culverts and concurrence with
the finding of effect. Implementation of the proposed project will not occur prior to the conclusion of the
Section 106 process. Further, in the event that currently unknown cultural resources are encountered
during project implementation, NRCS will ensure that the Section 106 process for post-review
discoveries (36 CFR § 800.13) is followed.
Finding: Less than significant impact.
Page 19 of 37
VI. GEOLOGY AND SOILS
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No Impact
Would the project:
a) Expose people or structures to potential
substantial adverse effects, including the risk of
loss, injury, or death involving:
x
i) Rupture of a known earthquake fault, as
delineated on the most recent Alquist-Priolo
Earthquake Fault Zoning Map issued by the State
Geologist for the area or based on other
substantial evidence of a known fault? Refer to
Division of Mines and Geology Special
Publication 42.
x
ii) Strong seismic ground shaking?
x
iii) Seismic-related ground failure, including
liquefaction?
x
iv) Landslides?
x
b) Result in substantial soil erosion or the loss of
topsoil?
x
c) Be located on a geologic unit or soil that is
unstable, or that would become unstable as a
result of the project, and potentially result in onor off-site landslide, lateral spreading,
subsidence, liquefaction or collapse?
x
d) Be located on expansive soil, as defined in
Table 18-1-B of the Uniform Building Code
(1994), creating substantial risks to life or
property?
x
x
e) Have soils incapable of adequately supporting
the use of septic tanks or alternative waste water
disposal systems where sewers are not available
for the disposal of waste water?
Discussion of Geology and Soils:
The proposed project site (both MP 8.60 and MP 8.75) are underlain by Cretaceous-age sedimentary
rocks of the Panoche Formation, with the rocks as marine sandstone, shale, siltstone and conglomerate
(C&A, 2013).
Seismic activity and associated hazards are present in the area and are summarized below. However, the
proposed project will not cause exposure to additional seismic risks, as no buildings or additional
infrastructure will be constructed (rather, existing, non-habitable infrastructure will be replaced and
Page 20 of 37
retrofitted).
The project site is not within a California Geologic Survey designated Earthquake Fault Zone (EFZ) and
no known “active” faults are shown to cross the project site on the most recent Alquist-Priolo Fault Zone
Map (C&A, 2013). The Hayward fault is located approximately 3.3 miles southwest and the Calaveras
fault is located approximately 2.9 miles northeast from the project site. The proposed project sites (MP
8.60 and MP 8.75) are subject to strong ground shaking from earthquakes on the nearby faults (Hayward
and Calveras). The sites are underlain by bedrock that is not susceptible to liquefaction and are not within
a California Geologic Survey designated Liquifaction Seismic Hazard Zone.
The project sites are located adjacent to slopes that are susceptible to earthquake-induced landslides and
are within a California Geologic Survey Earthquake-Induced Landslide hazard zone (C&A, 2013). The
site was investigated by a geotechnical engineer who concluded that the canyon slopes adjacent to the
project site are steep and subject to debris-flow type landslides that typically involve only the upper 5-10
feet (no evidence of deep-seated translational or rotational landslides more likely to impact the project
sites themselves was observed).
There is a potential for temporary erosion during construction activities. These impacts would be
associated with the dewatering of the stream and the potential for disturbance of fine sediment in the
stream associated with this project. However, the streambed and banks are primarily bedrock and
boulders and are not vulnerable to substantial soil erosion or topsoil loss.
Sediment control measures will be implemented as part of the dewatering process required for
construction. Any temporary dam or other artificial obstruction constructed will only be built from
materials such as sandbags or clean gravel which will cause little or no siltation. The dewatering channel
will be lined to prevent siltation into the water or a pipe will be utilized. Sand bags and any sheet plastic
will be removed from the stream upon project completion. Normal flows will be restored to the affected
stream immediately upon completion of work at that location. Best management practices will be
implemented to avoid increased sediment delivery to the stream during the construction work. The
project will comply with the provisions relating to the erosion as a source of surface water pollution
regulated by the Regional Water Quality Control Board.
No buildings or additional infrastructure will be constructed as a result of this project and therefore the
project will not impact people or property due to expansive soils, lateral spreading, subsidence or
collapse.
No structures will be constructed that will require wastewater management.
The primary concerns that led the sponsor, the Alameda County Resource Conservation District
(ACRCD), to propose the Stonybrook Creek project are: a) presence of barriers to migration of
anadromous steelhead and resident rainbow trout to identified spawning and rearing habitat in Stonybrook
canyon and b) a concern for damage to public infrastructure and private property due to undersized
crossings. Installation of the project will provide a net benefit to the stream through direct reduction in
soil loss and sedimentation through stabilization with a properly sized culvert for 100-year flows.
Finding: No Impact
Page 21 of 37
VII. HAZARDS AND HAZARDOUS MATERIALS
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project:
a) Create a significant hazard to the public or the
environment through the routine transport, use, or
disposal of hazardous materials?
x
b) Create a significant hazard to the public or the
environment through reasonably foreseeable
upset and accident conditions involving the
release of hazardous materials into the
environment?
x
c) Emit hazardous emissions or handle hazardous
or acutely hazardous materials, substances, or
waste within one-quarter mile of an existing or
proposed school?
x
d) Be located on a site which is included on a list
of hazardous materials sites compiled pursuant to
Government Code Section 65962.5 and, as a
result, would it create a significant hazard to the
public or the environment?
x
x
e) For a project located within an airport land use
plan or, where such a plan has not been adopted,
within two miles of a public airport or public use
airport, would the project result in a safety hazard
for people residing or working in the project
area?
f) For a project within the vicinity of a private
airstrip, would the project result in a safety
hazard for people residing or working in the
project area?
x
g) Impair implementation of or physically
interfere with an adopted emergency response
plan or emergency evacuation plan?
x
h) Expose people or structures to a significant
risk of loss, injury or death involving wildland
fires, including where wildlands are adjacent to
urbanized areas or where residences are
intermixed with wildlands?
x
Discussion of Hazards and Hazardous Materials: The proposed project does not involve handling,
creating or emitting any hazardous materials that may be released that may impact the environment or
community. The project is not located on or near a site that has been included on a list of hazardous
materials sites compiled through the Government Code Section 65962.5. Private airstrips are not within
Page 22 of 37
the immediate vicinity of the project site. Should an emergency response plan be initiated or evacuation
occur, the proposed project will not impact their implementation. As the project is located within a rural
canyon community lacking extreme fire hazardous vegetation and includes construction operations with
limited opportunities to iniate a fire, the project will not create a significant risk loss, injury or death
involving wildland fires that are adjacent to urbanized areas. Thus, no impacts to hazards and hazardous
materials are expected to occur through the proposed project.
Finding: No impact
Page 23 of 37
VIII. HYDROLOGY AND WATER QUALITY
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project:
a) Violate any water quality standards or waste
discharge requirements?
x
b) Substantially deplete groundwater supplies or
interfere substantially with groundwater recharge
such that there would be a net deficit in aquifer
volume or a lowering of the local groundwater
table level (e.g., the production rate of preexisting nearby wells would drop to a level
which would not support existing land uses or
planned uses for which permits have been
granted)?
x
c) Substantially alter the existing drainage pattern
of the site or area, including through the
alteration of the course of a stream or river, in a
manner which would result in substantial erosion
or siltation on- or off-site?
x
d) Substantially alter the existing drainage pattern
of the site or area, including through the
alteration of the course of a stream or river, or
substantially increase the rate or amount of
surface runoff in a manner which would result in
flooding on- or off-site?
x
e) Create or contribute runoff water which would
exceed the capacity of existing or planned
stormwater drainage systems or provide
substantial additional sources of polluted runoff?
x
f) Otherwise substantially degrade water quality?
x
g) Place housing within a 100-year flood hazard
area as mapped on a federal Flood Hazard
Boundary or Flood Insurance Rate Map or other
flood hazard delineation map?
x
h) Place within a 100-year flood hazard area
structures which would impede or redirect flood
flows?
x
i) Expose people or structures to a significant risk
of loss, injury or death involving flooding,
including flooding as a result of the failure of a
levee or dam?
x
j) Inundation by seiche, tsunami, or mudflow?
x
Page 24 of 37
Discussion of Hydrology and Water Quality.
The proposed project will meet standards for water quality. Groundwater supplies will not be adversely
affected by the proposed project. The proposed project will maintain or improve site drainage and reduce
potentials for erosion and siltation on- and off – site, as well as reduce potentials for flooding, both on and
off site.
The primary concerns that led the sponsor, the Alameda County Resource Conservation District
(ACRCD), to propose the Stonybrook Creek project are: a) presence of barriers to migration of
anadromous steelhead and resident rainbow trout to identified spawning and rearing habitat in Stonybrook
canyon and b) a concern for damage to public infrastructure and private property due to undersized
crossings. Therefore, long term impacts of the proposed project are positive, including reduction of
erosion contributing sediment to the watercourse. The new crossing at MP 8.60 will be properly sized so
that 100-year storm flows can adequately pass through, decreasing scour and reducing the occurrence of
storm flows that overtop the road and cause bank erosion. Hydraulic conditions affecting storm flow
volume and velocity through the crossing at MP 8.75 will not be significantly changed (as these are
controlled by the size of the inlet and will not be affected by the baffles) but the streambed will be graded
with step-pools and the steep drop at the inlet will be eliminated reducing the scouring of the stream bank.
Rock boulders along the bank in this location will be left in place to minimize future bank scour. Without
a full replacement of the culvert with an adequately sized bridge, boulders will continue to deposit
upstream of the MP 8.75 culvert. These boulders may eventually accumulate into a large pile again
although large storms are required to move boulders of that size (approximately 50-year or higher storm
events). A monitoring plan will be developed for the project site to evaluate the need for further action as
a result of any boulder movement.
Best management practices and erosion control measures will be used both during construction and in the
permanent erosion control measures to avoid adverse impacts to adjacent watercourses, hydrology, and
water quality. The project will adhere to water quality standards and the programmatic federal Clean
Water Act §401 Conditions and requirements as detailed by the San Francisco Bay Regional Water
Quality Control Board as part of the permitting process for this project. Compliance with prohibitions
provided by the San Francisco Bay Regional Water Quality Control Boards will mitigate any potential
adverse water quality impacts.
Implementation and maintenance of best management practices for erosion control measures and
pollution prevention will ensure that construction-related pollutants of concern, such as sediment and
petroleum products (see discussion on hazards and hazardous materials), do not adversely affect water
quality.
Finding: Less than significant impact
Page 25 of 37
IX. LAND USE PLANNING
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project:
x
a) Physically divide an established community?
b) Conflict with any applicable land use plan,
policy, or regulation of an agency with
jurisdiction over the project (including, but not
limited to the general plan, specific plan, local
coastal program, or zoning ordinance) adopted
for the purpose of avoiding or mitigating an
environmental effect?
x
c) Conflict with any applicable habitat
conservation plan or natural community
conservation plan?
x
Discussion of Land Use Planning: Not Applicable to this project.
Finding: No impact
X. MINERAL RESOURCES
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project
a) Result in the loss of availability of a known
mineral resource that would be of value to the
region and the residents of the state?
x
b) Result in the loss of availability of a locallyimportant mineral resource recovery site
delineated on a local general plan, specific plan
or other land use plan?
x
Discussion of Mineral Resources: No mineral resources have been identified at the site. Therefore, the
proposed project would have no impact on mineral resource availability.
Finding: No impact.
Page 26 of 37
XI. NOISE
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project result in:
a) Exposure of persons to or generation of noise
levels in excess of standards established in the
local general plan or noise ordinance, or
applicable standards of other agencies?
x
b) Exposure of persons to or generation of
excessive ground borne vibration or ground
borne noise levels?
x
c) A substantial permanent increase in ambient
noise levels in the project vicinity above levels
existing without the project?
x
d) A substantial temporary or periodic increase in
ambient noise levels in the project vicinity above
levels existing without the project?
x
e) For a project located within an airport land use
plan or, where such a plan has not been adopted,
within two miles of a public airport or public use
airport, would the project expose people residing
or working in the project area to excessive noise
levels?
x
f) For a project within the vicinity of a private
airstrip, would the project expose people residing
or working in the project area to excessive noise
levels?
x
Discussion of Noise: Temporary ambient noise levels in the project vicinity will increase during
construction activities (up to 8 weeks) but will not be permanent. The proposed project would not
expose persons to groundborne vibrations or noise. The Alameda County Noise Ordinance (6.60.070 –
Special Provisions or Exceptions – Paragraphs D and E) does not apply to construction or maintenance
and repair operations conducted by public agencies and/or utility companies or their contractors which
are deemed necessary to serve the best interests of the public and to protect the public health, welfare
and safety. The county ordinance does not apply to noise sources associated with construction, provided
said activities do not take place before seven a.m. or after seven p.m. on any day except Saturday or
Sunday, or before eight a.m. or after five p.m. on Saturday or Sunday. This project is covered under
these paragraphs. The construction contractor will comply with regulating construction noise to the
extent feasible and undertake efforts to minimize noise disruption to nearby neighbors and sensitive
receptors during construction. Construction activities will be limited to the time frame defined in the
ordinance. These effects are temporary and local in nature that will end with completion of the project.
The proposed project is not within an airport land use plan nor within two miles of an airport, or private
airstrip.
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Advance notification of construction, including name and phone number of Communications person
responsible for addressing noise complaints will be distributed to neighboring landowners. The same
information will be posted at construction sites.
Finding: Less than significant impact.
Page 28 of 37
XII. POPULATION AND HOUSING
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project:
a) Induce substantial population growth in an
area, either directly (for example, by proposing
new homes and businesses) or indirectly (for
example, through extension of roads or other
infrastructure)?
x
b) Displace substantial numbers of existing
housing, necessitating the construction of
replacement housing elsewhere?
x
c) Displace substantial numbers of people,
necessitating the construction of replacement
housing elsewhere?
x
Discussion of Housing: The proposed project would not construct additional infrastructure that would
lead to population growth nor would the project displace residents.
Finding: No impact
Page 29 of 37
XIII. PUBLIC SERVICES
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project:
a) Result in substantial adverse physical impacts
associated with the provision of new or
physically altered governmental facilities, need
for new or physically altered governmental
facilities, the construction of which could cause
significant environmental impacts, in order to
maintain acceptable service ratios, response times
or other performance objectives for any of the
public services:
Fire protection?
x
Police protection?
x
Schools?
x
Parks?
x
Other public facilities?
x
Discussion of Public Services: The restoration project will not require any additional public services,
nor require new governmental facilities.
Finding: No impact
Page 30 of 37
XIV. RECREATION
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
a) Would the project increase the use of existing
neighborhood and regional parks or other
recreational facilities such that substantial
physical deterioration of the facility would occur
or be accelerated?
x
b) Does the project include recreational facilities
or require the construction or expansion of
recreational facilities which might have an
adverse physical effect on the environment?
x
Discussion of Recreation: The restoration project will not increase the use of any recreational facility,
nor will it include the construction or expansion of such facilities.
Finding: No impact
Page 31 of 37
XV. TRANSPORTATION/TRAFFIC
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project:
a) Cause an increase in traffic which is
substantial in relation to the existing traffic load
and capacity of the street system (i.e., result in a
substantial increase in either the number of
vehicle trips, the volume to capacity ratio on
roads, or congestion at intersections)?
x
b) Exceed, either individually or cumulatively, a
level of service standard established by the
county congestion management agency for
designated roads or highways?
x
c) Result in a change in air traffic patterns,
including either an increase in traffic levels or a
change in location that results in substantial
safety risks?
x
d) Substantially increase hazards due to a design
feature (e.g., sharp curves or dangerous
intersections) or incompatible uses (e.g., farm
equipment)?
x
e) Result in inadequate emergency access?
x
f) Result in inadequate parking capacity?
x
g) Conflict with adopted policies, plans, or
programs supporting alternative transportation
(e.g., bus turnouts, bicycle racks)?
x
Discussion of Transportation and Traffic:
As the Stonybrook proposed project site is located along the County maintained and operated Palomares
Road, there will be short term impacts to resident access during the implementation process (up to 12
weeks). The proposed action requires temporary closure of one traffic lane and channeling vehicle traffic
during construction through a temporary bridge. Residents will face temporary delays and traffic control
during daytime hours and increased vehicle traffic from additional construction vehicles. It is anticipated
that the increase in traffic will not exceed the capacity of the street system.
Communication will occur with emergency responders during construction to facilitate emergency access.
Coordination has been completed with local emergency responders to ensure that access is adequate for
emergency vehicles throughout the project.
The traffic and transportation changes from the Stonybrook proposed project will primarily affect the
landowners within the immediate vicinity of the Stonybrook proposed project site and Stonybrook
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Canyon. However, Palomares Road does not receive high traffic flows or rush hour traffic. Community
meetings will be held prior to construction activities and signage will be posted noting scheduled
construction to minimize automobile traffic during construction hours. Long term effects are beneficial
as the culvert improvements will reduce the probability of emergency road closure due to floods.
Finding: Less than significant impact.
Page 33 of 37
XVI. UTILITIES AND SERVICE SYSTEMS
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
No
Impact
Would the project:
a) Exceed wastewater treatment requirements of
the applicable Regional Water Quality Control
Board?
x
b) Require or result in the construction of new
water or wastewater treatment facilities or
expansion of existing facilities, the construction
of which could cause significant environmental
effects?
x
c) Require or result in the construction of new
storm water drainage facilities or expansion of
existing facilities, the construction of which
could cause significant environmental effects?
x
d) Have sufficient water supplies available to
serve the project from existing entitlements and
resources, or are new or expanded entitlements
needed?
x
e) Result in a determination by the wastewater
treatment provider which serves or may serve the
project that it has adequate capacity to serve the
project's projected demand in addition to the
provider's existing commitments?
x
f) Be served by a landfill with sufficient
permitted capacity to accommodate the project's
solid waste disposal needs?
x
g) Comply with federal, state, and local statutes
and regulations related to solid waste?
x
Discussion: The proposed project would not result in the use, construction or expansion of water supply,
storm water, wastewater or solid waste facilities. No impacts to utilities or service systems would result
from this project.
Finding: No Impact
Page 34 of 37
XVII. MANDATORY FINDINGS OF SIGNIFICANCE
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact
a) Does the project have the potential to degrade
the quality of the environment, substantially
reduce the habitat of a fish or wildlife species,
cause a fish or wildlife population to drop below
self-sustaining levels, threaten to eliminate a
plant or animal community, reduce the number or
restrict the range of a rare or endangered plant or
animal or eliminate important examples of the
major periods of California history or prehistory?
No
Impact
x
b) Does the project have impacts that are
individually limited, but cumulatively
considerable? ("Cumulatively
considerable" means that the incremental effects
of a project are considerable when viewed in
connection with the effects of past projects, the
effects of other current projects, and the effects
of probable future projects)?
x
c) Does the project have environmental effects
which will cause substantial adverse effects on
human beings, either directly or indirectly?
x
Discussion of Mandatory Findings of Significance: The Stonybrook Creek Fish Passage Improvement
Project in Stonybrook Creek will not degrade the quality of the environment, substantially reduce habitat
for fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels,
threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or
endangered plant or animals, or eliminate important examples of the major periods of California history
or prehistory. Such a potential does not exist because the project will be implemented in such a manner as
to avoid short-term impacts to sensitive resources. The project has no potential to adversely impact
human beings. The project impacts on cultural resources associated with the bridge replacement are less
than significant. The project does not have the potential for adverse cumulative impacts. The project will
result in improvement in hydraulic function, water quality, and natural habitat for the Central Coast
California steelhead trout and resident rainbow trout (Oncorhynchus mykiss).
Finding: Less than significant impact
Page 35 of 37
SECTION 3.0 REPORT PREPARATION
Lead Agency
Alameda County Resource Conservation District is the lead agency under CEQA for the proposed
project. Copies of the MND are available for review at the ACRCD from Friday January 17, 2014
through Friday February17, 2014 Monday through Fridays between the hours of 9:00 am and 5:00 pm.
Project Sponsors
The Alameda County Resource Conservation District
The mission of the Alameda County Resource Conservation District (ACRCD) is to provide leadership in
Alameda County and the region about natural resources conservation and agricultural issues (the working
landscape) through education, outreach, resource services, partnerships, and funding. The fundamental
principles of natural resources conservation, the working landscape, and agricultural heritage guide the
ACRCD’s programs and activities. Since 1972, ACRCD has administered government and private
foundation grants for watershed-wide planning, erosion control, and restoration projects. ACRCD
continues to bring together state, federal, and local agencies with private landowners to conserve soil and
water resources, with projects focusing on the following topics:






Control of soil erosion
Riparian habitat restoration
Protection and improvement of water quality
Education and outreach
Conservation of rangeland and cropland
Active support of the district's agricultural economy and heritage
The California Public Resources Code (PRC) specifically empowers any Resource Conservation Districts
(RCD) to manage soil conservation, water conservation, erosion control, erosion prevention, or erosion
stabilization projects (PRC §9415). The code also allows an RCD, with the consent of affected private
property owners, to make improvements or conduct operations that will further water conservation and
the prevention and control of soil erosion (PRC §9415).
The U.S. Department Of Agriculture Natural Resources Conservation Service
The Natural Resources Conservation Service (NRCS), ACRCD’s federal partner for the project, provides
technical assistance and cost-sharing to cooperators (private landowners working in partnership with the
ACRCD/NRCS) to develop conservation systems uniquely suited to their land and individual way of
doing business. NRCS, formerly the Soil Conservation Service, builds on the strength of more than 60
years of natural resource protection on private lands. The agency works closely with local RCDs and
other agencies, organizations, and individuals to set conservation priority goals, work with people on the
land, and provide assistance. NRCS sponsors important conservation incentive programs to preserve
natural resources including Wildlife Habitat Incentives Program (WHIP), Conservation Reserve Program
(CRP), and Environmental Quality Incentives Program (EQIP).
Page 36 of 37
References
Alameda County Water District (ACWD). Alameda County Water District webpage: Current Fish
Passage & Related Projects. http://www.acwd.org/index.aspx?NID=456 (accessed 7/10/2013).
Alexander, Pete. 2006. Stonybrook Creek Visual Survey Notes. East Bay Regional Park District, Alameda
Creek Alliance.
Alexander, Pete, Leigh Ochikubo Chan, Sal Lopez. 2008. Stonybrook Creek Visual Survey Notes. East
Bay Regional Park District, Alameda County Water District, Alameda Creek Alliance.
Becker, Gordon. Center for Ecosystems Management and Restoration. 2013. Results of Stonybrook Creek
pool/spawning habitat survey and fish sampling.
California Department of Fish and Wildlife. CNDDB (California Natural Diversity Data Base). 2013.
Sacramento, CA. http://www.dfg.ca.gov/biogeodata/cnddb/
Crawford & Associates (C&A). Geotechnical Report Amendment: Stonybrook Creek Crossings
Improvements. 2013. San Francisco, CA.
GHD, Inc. 2013. Stonybrook Creek Crossings Improvements Project: 50% Basis of Design Report.
Jones and Stokes. 2006. Working Draft: Santa Clara Valley HCP/NCCP South/Central California Coast
Steelhead (Oncorhynchus mykiss) Species Account.
Michael Love & Associates (MLA). 2001. Stonybrook Creek Fish Passage Assessment. Prepared for
Alameda County Public Works Agency.
Michael Love & Associates (MLA) and Center for Ecosystems Management and Restoration. 2005a. Fish
Passage of Private Stream Crossings on Lower Stonybrook Creek.
Michael Love & Associates, Winzler & Kelly (W&K), Center for Ecosystem Management and
Restoration. 2005b. Stonybrook Creek Salmonid Migration Barrier Removal Project.
Michael Love & Associates (MLA). 2010. Stonybrook Creek Watershed: A Strategic Plan for
Eliminating Barriers to Steelhead Migration. http://www.alamedacreek.org/reportseducational/pdf/ACFCD%202010.pdf
Michael Love & Associates (MLA). 2013. Technical Memorandum: Feasibility of fish passage retrofit
options for two Palomares Road crossings on Stonybrook Creek.
The references cited above are to published material and specific items of information obtained by NRCS
from other organizations and individuals. Other supplemental information is in supporting documents
and project files. Anyone who wishes to review this material may arrange to do so by contacting one of
the following offices:
ACRCD/NRCS Livermore Local Partnership Office: 3585 Greenville Rd, Ste 2, Livermore CA 94550;
(925) 371-0154.
NRCS Davis (State) Office: (c/o Design Staff) 430 G Street, Davis CA 95616; (530) 792-5612.
Page 37 of 37