Proposal: Tahoe Research Supported by SNPLMA 2010
I Ttl
I e Page
Title:
Laboratory experiments on fine particle capture by submerged
vegetation in stream environment zones (SEZs): The effects of
vegetation density, biofilm development and particle
composition
Subtheme:
2c: Quantifying the effects of actions to reduce sediment loads using
Stream Environment Zones (SEZs)
S. Geoffrey Schladow
UC Davis, Tahoe Environmental Research Center
One Shields Ave, Davis CA 95616
Phone: 5307523942
Fax:
Email: gschladowcmucdavis.edu
Principal Investigator and
Receiving Institution
Co-Principal Investigator
<add more rows as needed>
Agency Collaborator
Hannah Schembri
Lahontan Regional Water Quality Control Board
Email: HSchembri@waterboards.ca.gov
Jason Kuchnicki
NDEP
Email: jkuchnic@ndep.nv.gov
Shane Romsos
TRPA
Email: sromsos@trpa.org
Grants Contact Person
Funding requested:
Total cost share (value of
David Miller
Office of Research/Sponsored Programs
1850 Research Park Drive, Ste 300
Davis, CA 95618
Phone: 5307548206
FAX: 530 754 8229
davmillerrmucdavis.edu
$ 195,213
$
financial and in-kind
contributions) :
3
Proposal: Tahoe Research Supported by SNPLMA 2010
II. Proposal Narrative
a. Project abstract
This proposal focuses on the measurement of fine particle capture efficiencies in a laboratory
flume using analogs of the vegetation present in an SEZ. The laboratory flume offers the ability to vary
flow rate, substrate density (stems per square meter), stem width, particle concentration, and
presence/absence of biofilms (biological surface coatings) in a repeatable fashion and to measure the
changing particle size distribution and particle concentration over time. The size-specific removal
efficiencies that can be calculated in this way can then be used as the basis for assigning removal
efficiencies in any SEZ in the Tahoe basin, based on site-specific flowrate, vegetation type and density,
and initial particle concentration. The values can also be used as part of a comprehensive strearn/SEZ
model and provide more detailed estimates of the effectiveness of SEZs in achieving restoration goals.
The output from the proposed study can be used as the basis of site selection for future capital projects
involving the use of SEZs for fine sediment removal, as the basis for assigning credits to project
implementers for particle and nutrient removal, and as the basis for the design of sophisticated pump-back
systems where flow through "treatment SEZs" could be controlled to better maximize fine particle
removal.
b. Justification statement:
The sub-theme, "Quantifying the effects ofactions to reduce sediment loads using Stream
Environment Zones", seeks to provide management and regulatory agencies with tools and
methodologies to quantify the direct effects of SEZ restoration projects in achieving pollutant load
reductions targets for Lake Tahoe. "Specifically, estimates ofthe direct effects ofSEZ restoration projects
to achieve TMDL reduction goals are needed".
Stream Environment Zones (SEZs) by their nature only impact sediment removal at times of
increased stream flow and stage, when sediment-laden streamwater is flowing through a cross-section
comprised of both bare stream channel and the vegetated overbank area. While sediment transport
relationships for the bare stream channel are well understood, the removal of fine sediment (and
associated nutrients) by the vegetation is poorly understood. While models may purport to represent the
removal efficiency, they are based on an assumed "removal efficiency" or "capture efficiency" that has
little theoretical or experimental foundation. Many models simply ignore the important processes related
to particle removal. Measuring the capture efficiency in the field is exceedingly difficult, in large part
because it entails having the right equipment deployed when a flow event of interest occurs. Even then,
the input flow rates and sediment concentrations represent just a single storm event, and provide no basis
for inferring removal efficiencies under different conditions.
This proposal focuses on the measurement of fine particle capture efficiencies in a laboratory
flume using analogs of the vegetation present in an SEZ. As has been demonstrated in preliminary tests,
the laboratory flume offers the ability to vary flow rate, substrate density (stems per square meter), stem
width, particle concentration, and presence/absence of biofilms (biological surface coatings) in a
repeatable fashion and to measure the changing particle size distribution and particle concentration over
time. The size-specific removal efficiencies that can be calculated in this fashion can then be used as the
basis of assigning removal efficiencies in any SEZ in the Tahoe basin, based on site-specific flowrate,
vegetation type and density, and initial particle concentration. Alternatively, the values could be used as
part of a comprehensive stream/SEZ model and provide more detailed estimates ofthe effectiveness of
SEZs in achieving restoration goals.
The output from the proposed study could be used as the basis of site selection for future capital
projects involving the use of SEZs for fine sediment removal, as the basis for assigning credits to project
implementers for particle and nutrient removal, and as the basis for the design of sophisticated pumpback
systems where flow through "treatment SEZs" could be controlled to better maximize fine particle
removal.
3
Proposal: Tahoe Research Supported by SNPLMA 2010
c. Concise background and problem statement
A great deal of attention has been paid to understanding the dynamics of suspended solids in
engineered systems for wastewater treatment (e.g. Levine, Tchobanoglous et al. 1985), and environmental
systems like lakes, reservoirs, rivers, etc. for reasons ranging from hydropower, to transport of larval
organisms (e.g. Finger, Schmid et al. 2006; Pfandl and Boenigk 2006; Palmarsson and Schladow 2008).
However, limits to computational capacity and laboratory analytic techniques in addition to the
complexity of wetland systems have limited both laboratory and modeling investigations of fine particle
dynamics until recently. Developments in a variety of fields have recently generated methods capable of
assessing concentrations and particle size distributions (PSD) of extremely fine particles «10 /lm in
diameter) (Agrawal, Pottsmith et al. 1996).
Particle capture in aquatic systems is the process by which particles in suspension impact and are
retained on submerged surfaces. This process is highly relevant to biological cycles involving seed
dispersal and recruitment and plays a large role in the fate and transport of chemicals in aquatic
environments (Harvey et al. 1995). Particle capture is also important in environmental engineering
applications because of the large effect it may have on general water quality in wetlands and stream
environmental zones. For SEZs with relatively dense vegetation and high water velocities, the process
can significantly reduce downstream transport of suspended solids and any contaminants or nutrients
associated with them (Palmer et al. 2004).
There are numerous reasons why SEZs and floodplains are effective for removal of suspended
sediments. It is well established that flow within these regions is much slower than in the main stream
channel and the increased residence time aids in particle removal. Additionally, studies have shown that
floodplains with vegetation removes substantially more suspended material than floodplains without
(Kadlec 1996). Initially, the process driving vegetative particle removal was modeled as purely physical
(Palmer, Nepf et al. 2004). However, settling and direct impact of vegetation by particles are small
compared to observations of bulk removal in wetlands. Modeling efforts have managed to capture many
of the processes associated with hydrodynamics in flood plains (Nepf 1999; Nepf and Vivoni 2000) and
recent studies have tried to elucidate processes related to particle capture in such systems (Jin and
Romkens 2001; Palmer, Nepf et al. 2004). However, the process by which vegetation acts as an effective
particle remover remains ill-defined.
In engineering water quality models particle capture by submerged vegetation is an overlooked
mechanism. Often it is combined with the process of gravitational settling, and suspended sediment
reductions are parameterized using a single bulk removal rate. Other studies have assumed it to be
insignificant, based on the results of one field and lab study performed in 1992 (Kadlec and Knight, 1996;
Hokosawa and Horie, 1992). However more recent laboratory examinations have shown that particle
capture is indeed a significant and mechanistically separate process from settling that must be accounted
for in wetland and SEZ models. A simple calculation bears this out. The particle flux for a unit area of
SEZ due to gravitational settling can be represented as settling = Vs C , where Vs is the particle settling
velocity and C is the particle concentration. Flux due to vegetative particle capture may be represented as
capture = h U A v C , where U is the flow velocity, A v is the cross sectional area of the vegetation
projected normal to the flow direction per unit ground area, and h is the capture efficiency. The ratio of
capture to settling fluxes is equal to h (U/Vs) A v , a number that can be used to assess the importance of
particle capture relative to settling for a range of wetland conditions. In SEZ environments, for example,
representative efficiencies (0.001), water velocities (0.1 m/s), settling velocities (0.01 mrn/s), and
vegetation area indices (0.1-1.0) indicate that capture fluxes are 1-10 times as important as settling fluxes.
Water quality models for submerged environments should therefore explicitly consider particle capture in
order to better represent the mechanisms responsible for water quality improvement and to accurately
predict the system response to changes in vegetation.
4
Proposal: Tahoe Research Supported by SNPLMA 2010
In the equation for capture flux given above, the capture efficiency h is defined as the ratio of 1) the
upstream width of streamlines for which a particle traveling on will impact a vegetative surface to 2) the
width of the vegetative surface (Figure I). The efficiency is used to relate the cross sectional flow area
resulting in capture (needed for flux calculations) to the cross sectional flow area approaching vegetation
(which can be more easily measured). Detailed laboratory studies have recently been performed by
Palmer et al. (2004) and Purich (2006) to attempt to quantify the dependence of capture efficiency on
variables such as the flow velocity, vegetation stem width, particle diameter, and vegetation density.
However for both these studies, vegetation was modeled using plastic cylinders coated in silicone grease
so that the plastic particles used would stick with 100% efficiency when impacting a surface. This grease
2
coating was explained as representative ofthe sticky biofilms that grow on submerged vegetation • In
SEZ environments, however, overbank vegetation is originally dry and biofilms must develop over the
course ofa flood event. Before and during the establishment of these biofilms, capture efficiencies are
likely to be lower than what has been previously measured in the lab.
The focus of the lab experiments proposed here will be to elucidate the dependence of particle capture
efficiency on the following key variables: Stem density and thickness, flow rate, biofilm development,
particle size distribution and particle composition. Previous lab experiments have examined the
'kinematic' particle capture efficiency related to streamlines passing within one particle radius of
vegetation surfaces. The lab experiments introduced here will examine the combined kinematic
efficiency and' impact' efficiency, the ratio of particles that impact and are taken out of suspension by
particle capture to those that only impact the surface. Impact efficiency was assumed to be 100% in
previous studies, but is hypothesized in natural environments to be dependent on the composition of the
impacting particle and the presence or thickness of a biofilm on the submerged surface. Unlike the plastic
particles used in previous lab experiments, natural particles may be aggregates of organic and inorganic
material and may vary in their likelihood to be retained on submerged surfaces lacking a sticky biofilm. In
addition, by directly measuring the concentration of particles within multiple size classes using the
LISST, we will be able to distinguish the "apparent loss" of fine particles that occurs as very fine particles
aggregate to form larger particles. This is referred to below as size evolution.
d. Goals, objectives, and hypotheses to be tested
GOALS
(1) Conduct laboratory experiments to determine the fine particle capture efficiency of flows through
SEZs under the range of controlling variables that are experienced in the Lake Tahoe basin.
(2) Develop relationships to estimate particle capture efficiency as a function of the controlling variables
(3) Pilot test the relationships for conditions in Trout Creek and the Upper Truckee River
OBJECTIVES
1. Produce a matrix of experimental variables to be tested in the laboratory flume. The variables include
flow rates, particle size distribution, particle concentration, particle type, stem density, stem diameter, and
condition and/or presence of biofilm.
2. Use existing data, especially the recently acquired basin lidar data and multispectral satellite data to
determine the vegetation height, density and type in SEZs ofthe Upper Truckee River and Trout Creek.
3. Field ground truthing to ascertain stem diameters and areal density.
4. Use historical flow and stage data to determine the range of flow conditions, and historical storm water
and stream water data to determine the expected range of particle size distributions and concentrations.
5. Construct modular "test beds" of stems using dowels or other inert materials that encompass the
density and size range needed.
6. Extend the preliminary experiments on growing biofilm on dowels
7. Modify existing flume to maintain water temperature during experiments
8. Conduct flume experiments
5
Proposal: Tahoe Research Supported by SNPLMA 2010
9. Analyze results to detennine particle capture efficiency and particle size evolution
10. Detennine main variables controlling particle capture and size evolution
II. Using relationships developed, detennine particle capture efficiency and size evolution for Trout
Creek and the Upper Truckee River
12. Compare predictions from the methodology to existing data from Trout Creek and the Upper Truckee
River
13. Work collaboratively with projects aimed at developing SEZ models, to improve and to help calibrate
those models (see Section II-f.)
14. Develop recommendations for maximizing particle capture and size evolution on Trout Creek and the
Upper Truckee River.
HYPOTHESES
(1) Particle capture efficiencies for bare dowels are smaller than biofilm-coated dowels
(2) For every dowel density and diameter, there is an optimal flow rate for maximizing particle capture
and size evolution
(3) The mechanism of particle capture by biofilms exceeds particle loss by settling
(4) The mechanism of particle capture by biofilms exceeds particle "loss" by size evolution
(5) Particle composition changes the rate of particle capture
e. Approach, methodology and location of research
Experiments will examine, in a laboratory environment, the capture efficiencies for different
particle size classes (from 2.5 flm to larger than 63 flm) and different origin (stonnwater, streamwater,
synthetic particles etc.). Figure 2 shows sample of the particle size distributions used in the preliminary
experiments. For all experiments, capture efficiency will be measured by allowing suspended particles to
collect on vegetation modeled as wooden dowels in a recirculating tank. Experiments will be conducted
in a prismatic 7 ft long by 11 in high by 6.5 in wide flume with recirculating water passing through an
array of preconditioned wooden dowels. The water velocities will be measured with an acoustic Doppler
velocimeter (Son-Tek) and suspended sediment concentrations and particle size distributions will be
recorded using a flume mounted LISST-1 OOX laser in-situ diffraction particle sizer (Sequoia Scientific,
Inc.) and filtered grab samples. This instrument has been used to measure particle size distributions for
Lake Tahoe water and stream water in the past, making the methodology totally comparable to past
measurements. The experimental setup is illustrated in Figure 3.
Preliminary experiments undertaken during summer 2010 tested the methodology and helped
refine the hypotheses listed above. Table I lists the preliminary experiments that were conducted. Figure
4 shows some ofthe data from those preliminary results. It is important to note the removal rate of
particles (the upper two curves) and the improvement in light transmission (the lower two curves)
Table 1: Summary of all runs and experimental trials showing initial particle concentrations, flow
rate, velocity and optical transmissions. (Nover et al., unpublished data).
6
Proposal: Tahoe Research Supported by SNPLMA 2010
Run #
Date
Run 1
Run 2
Run 3
Run 4
Run 5
Run 6
Run 7
Run 8
Run 9
Run 10
Run 11
Run 12
Run 13
Run 14
Run 15
Run 16
Run 17
Run 18
9/8110
9/10/10
9.113/10
9113/10
9114110
9/14T10
9/15/10
9115110
9/17110
9117110
9120/10
9/20110
9121/10
9/21110
9/23110
9/23110
9124f10
Test nme (min.) Particle Type
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
120
60
60
Clay
Clay
Road dust
Road dust
Road dust
Road dust
Clay
Clay
Organic Particles
Organic Particles
Clay
Clay
Organic Particles
Organic Particles
Road dusl
Road dust
Organic Particles
Oraanic Particles
Q [10-3 m; S·']5 v [10·l m s·~t
Treatment
No Dowels
No Dowels
No Dowels
No Dowels
Dowels no biofilm
DoW€ls no biofilm
DOI'/€Is no biofilm
Dowels no biofilm
Dowels no biofilm
Dowels
Dowels wilh 6iofilm
Dowels with 6iofilm
No Dowels
No Dowels
Dowels with Biofilm
Dowels with Biofilm
Dowels with Biofilm
Dowels with BiQfilm
1
096
0.85
0.96
0.70
0.96
0.87
± 0.16
t 012
% 013
± 0.17
± 0.26
± 039
1
0.81 ± 023
1
0.84
0.82
0.90
0.80
0.81
0.78
0.85
0.80
± 032
± 035
± 012
± 0.12
±
±
±
±
0.26
025
020
016
373
4.13
399
4.25
B7
5.54
4.25
380
416
3.96
4.23
3.69
405
3.82
398
4.10
4.16
4.00
Starting Optical
Starting
Transmission [%J4 Concentration [pI/if
± 0.35 80.78 ±
0.35 69.30 %
%OA5 72.56 %
± OAl 68.81 %
± 0.49 72.62 ±
± 0.49 63.44 ±
± 1.09 66.33 ±
± 0.80 71.01 ±
± 0.46 74.88 ±
± 0.47 70.63 ±
± 0.70 68.26 ±
± 0.61 66.04 ±
± 035 72.98 %
± 0.29 70.34 ±
± 0.61 68.29 %
± 0.49 65.09%
± 0.46 70.57 ±
± 0.60 71.42 ±
t
0.15
0.12
0,36
0.36
0.21
0.22
0.21
0.27
0.15
0.26
0.48
0.39
0.28
016
014
028
0.15
0.08
9/24110
1 No Flow profile Data recorded
M assum~ton was made that Ihe vertical flow in the flume is homogenous in terms of "'idth (152 em) and length (212 em).
2 Eech ADV profile was recorded for 7minutes at a sam~ing rate of 25 Hz. Velocity profiles were taken at aheight of 7.8 em.
l at 78 em height' during run
~ Considered are the first six Lisst measurements after each start of arun
5 Uncertainties are Qf-len as one standard d8'liation
4.27 ±
lAG %
18.90 ±
21.99 ±
1798 ±
1947 ±
11.53 ±
931 t
14.26 ±
19.44 ±
13.86 ±
1119 ±
13.49 ±
16.05 ±
22.70 ±
24.85 %
16.91 ±
15.72 ±
0.34
049
0.90
1.30
0.55
055
1.23
1.18
1.19
077
1.83
1.27
0.71
0.80
0.55
1.14
0.71
0.62
The first set of experiments that will be undertaken as part of this proposed work will test the effect of
suspended particle composition on capture efficiency. River water from the Upper Truckee River and
Trout Creek (both located in the Lake Tahoe Basin, CA) will be used as representative of a natural river
particle distribution. For each experiment, approximately 20 gallons of water will be taken and placed in
the flume setup. Additional river water samples will be taken, filtered in series to obtain mass
concentrations for each particle size class, and then analyzed for organic/inorganic content within each
class. A final set of water samples will be analyzed using the LISST to determine particle settling
velocities. The recirculating flume will be run using water containing the natural particle distribution for
approximately 5 hours during which a flume mounted LISST will provide time series concentrations for
each size class. The LISST time series data along with the previously determined settling velocities will
be used to calculate capture efficiencies. Using a mass balance approach, it will be possible to determine
if particles have disappeared from the water by adhering to the biofilms, or whether fine particles have
disappeared because they have aggregated to form larger particles (particle size evolution). This
experiment will be repeated using different water velocities, source waters, and dowel array densities
(number of dowels per flume area, diameter of dowels), and the resulting efficiencies will be compared to
those previously measured by researchers assuming a 100% impact efficiency. The data on particle
organic/inorganic fractions will be examined for correlation with the deviation from 100% impact
efficiency. It is hypothesized that the smaller size classes will contain a lower organic/inorganic ratio and
be less likely to stick to the wooden dowel collectors.
For those particle size classes with significantly lower capture efficiencies than what would be
expected with a 100% impact efficiency, additional experiments will be run to determine the effect of
biofilm establishment collection efficiency. These experiments will use silica beads of a single particle
size class. The beads in suspension will be run through an array of dowels in the recirculating flume for
approximately 5 hours, and the flume mounted LISST will be used along with a settling velocity
7
Proposal: Tahoe Research Supported by SNPLMA 2010
experiment to calculate the particle capture efficiency, as before. An independent calculation of particle
capture efficiency will be made by scraping and rinsing impacted material from the surface of several
dowels and analyzing it for particle concentration using the LISST. Following the experiment to measure
capture efficiency, the water in the tank will be left to circulate at slower velocities for a period of
approximately I week during which a natural biofilm will be allowed to establish on the surface of the
dowels. Measures of biofilm abundance per unit surface area will be made by scraping material off
several dowels and analyzing it for chlorophyJl-a concentration and dry weight. The particle capture
experiment will then be repeated and a new particle capture efficiency will be calculated. This process
will be repeated for several weeks to allow the biofilm growth to proceed and fully examine the effect of
biofilm establishment and development on particle capture efficiencies. Further experiments will be
conducted on using highly eutrophic water to grow biofilm on the dowels ahead of time to accelerate the
experimental cycle.
f. Relationship of the research to previous and current relevant research, monitoring, and/or
environmental improvement efforts
The research is directly linked to ongoing research supporting environmental improvement
projects in the Tahoe Basin. The PI is currently leading a study to model and measure floodplain
processes in the T~out Creek watershed. Part of that project was to measure particle retention by
floodplain vegetation during flood events. Despite two years of preparations for flood events, Trout Creek
did not flood and the necessary data could not be collected. That experience highlighted the difficulty of
trying to collect these types of data under field conditions. The present proposal seeks to obtain similar
data under fully controllable conditions, in the expectation that future and ongoing field measurements
(by others) can then be used to compare with the lab data and the extension to a broader range of flow and
environmental conditions will be possible.
The PI is also conducting a field study on biofilm development and particle capture in a storm
water detention basin (Cattleman's Basin). These studies are very closely tied. In particular the
Cattlemen's study will help inform the question of how quickly a biofilm gets established on natural
vegetation. Data from this experiment is scheduled to be collected during the winter/spring of 2010/2011
and so will be able to inform the design of the proposed lab experiments. It needs to be borne in mind,
however, that the conditions in the storm water detention system and a functioning natural SEZ are very
different, both in terms of the flowrate, the particle size distribution and concentration, and the type and
density of submerged vegetation.
There is currently a wetland condition assessment project taking place in the Tahoe Basin (under
EPA funding) that is intended to include SEZs. The PI and the project team will communicate with that
project team to ensure that there is consistency in the vegetative designations they are developing and the
ones we are determining from the lidar and multispectral data, and to take full advantage of any relevant
results they may have.
The PI is intimately familiar with all the research that has gone into the development of the
TMDL (being the leader of the lake modeling component) and heading past and current measurements of
particle size distribution in the lake and the monitored streams that flow into Lake Tahoe. The PI is
keenly aware of the needs of both the agencies for methodologies to design and site BMPs, and the
concerns of local implementers that they receive due credit for installing projects that really do reduce the
particle load to the lake. The PI also is aware of the need for rapidly establishing confidence in the
particle removal efficiencies associated with all restoration projects, so that monitoring can be reduced to
an acceptable level and thereby conserve resources.
A separate proposal for SNPLMA funding for modeling SEZs is being submitted by colleagues at
DRI Las Vegas (Dr Li Chen). It is our joint intention to collaborate if both proposals are funded.
8
Proposal: Tahoe Research Supported by SNPLMA 2010
g. Strategy for engaging with managers and obtaining permits
Permitting is not required for any of the activities to be undertaken as part of this project.
The PI has established a sound working relationship with agency staff throughout the Tahoe
Basin, and has already engaged them concerning the lack of this type of data. In the past TERC staff and
students have participated in workshops on SEZ modeling that were intended to engage managers, and we
will continue participating in such activities. Specifically for this project, we have budgeted on three
meetings - one at the initiation of the project, and then meetings at 6 monthly intervals. These meetings
may be either restricted to a small sub-set of agency managers, or may be included as part of larger
science-agency meetings that occur regularly in the Tahoe Basin (e.g. SMIT, UTRWAG).
The purpose of the proposed laboratory experiments is to obtain data that are urgently needed for
computer models of SEZs, floodplains and wetlands. As data become available through this project, we
are prepared to keep agency managers and others working on the development of such models fully
apprised of our progress.
h. Description of deliverables/products and plan for how data and products will be reviewed and
made available to end users
The principal project deliverables will be
1. A final report that provides a full description of the experiments and the data. The report will
provide values for capture efficiency of fine particles for the range of conditions found in Trout
Creek and the Upper Truckee River.
2. Maps ofthe Upper Truckee River and Trout Creek showing SEZ physical (slope) and vegetation
(diameters and densities) designations developed for lab experiment purposes and capture
efficiencies as a function of position along each stream.
3. Draft manuscripts for submission to peer-reviewed journals (we are aiming to produce two
papers)
4. Presentations to Agency managers/staff at approximately month 9 and month 18.
5. Develop recommendations for maximizing particle capture and size evolution in SEZs in the
Tahoe Basin.
9
Proposal: Tahoe Research Supported by SNPLMA 2010
III. Schedule of major milestones/deliverables
Projects should not expect to begin before June 2011. Note that it is the responsibility of
the project proponent to coordinate with appropriate agency representatives or partners and
secure any agreements or approvals necessary prior to initiating research. Be sure to include
adequate time for submitting draft deliverables for review, responding to reviews, and submitting
final deliverables.
MilestonelDeliverables
Prepare progress
reports·
Start Date
Oct2011
Annual
accomplishment report
Sep 2011
Commence Project
July 2011
Modify flume
July 2011
Aug 2011
Water cooling system addition to allow
longer experiments
Lidar/Multispectral
data analysis
Ju1y2011
Aug 2011
Field ground
truthing
July 2011
Aug 2011
Extract canopy information and vegetation
type from summer 2010 lidar data and
multispectral satellite data
For representative vegetation types,
confirm stem diameters and areal densities
Lab Experiment
Design Matrix
Aug 2011
Sep 2011
Flume experiments
Oct 2011
Dec 2012
Data Analysis
Jan 2012
Reports/Papers
Sep 2011
Analysis of LISST particle size data,
velocity data, biofilm particle capture data,
photographic data
June 2012 Goal is for final report and two draft
manuscripts for peer reviewed publication
End Date
July 2013
Description
Submit brief progress report to Tahoe
Science Program coordinator by the 1st of
July, October, January, and April.
Sep 2012 Prepare annual summary of
accomplishments in September.
Meeting with primary stakeholders to
prioritize deliverables
Mar 2013
10
Produce matrix of experiments to be
conducted to cover all independent
variables over appropriate range. Design
and fabricate dowel inserts to confirm with
field data. Modify pump as necessary to
obtain correct flow rates.
Conduct flume experiments, biofilm
growth and removal experiments
Proposal: Tahoe Research Supported by SNPLMA 2010
IV. References
Agrawal, Y. c., H. C. Pottsmith, et al. (1996). "Laser instruments for particle size and settling velocity
measurements in the coastal zone." 'Prospects for the 21 st Century' Conference Proceedings.
OCEANS 96 MTS/IEEE (Cat. No.96CH35967)I'Prospects for the 21st Century' Conference
Proceedings. OCEANS 96 MTS/IEEE (Cat. No.96CH35967): 10.11 09/0CEANS.1996.569062.
Finger, D., M. Schmid, et al. (2006). "Effects of upstream hydropower operation on riverine particle
transport and turbidity in downstream lakes." Water Resources Research 42(8).
Harvey, M, E Bourget, and RG Ingram. 1995. Experimental evidence of passive accumulation of marine
bivalve larvae on filamentous epibenthic structures. Limnology and Oceanography, 40, 94-104.
Hokosawa, Y, and T Horie. 1992. Flow and particulate nutrient removal by wetland with emergent
macrophytes. Science for the Total Environment, Supplement, 1271-1282.
Jin, C. X. and M. J. M. Romkens (2001). "Experimental studies offactors in determining sediment
trapping in vegetative filter strips." Transactions of the Asae 44(2): 277-288.
Kadlec, RH, and RL Knight. 1996. Treatment Wetlands. New York, NY: Lewis Publishers.
Levine, A. D., G. Tchobanoglous, et al. (1985). "Characterization of the size distribution of contaminants
in waste-water - treatment and reuse implications." Journal Water Pollution Control Federation 57(7):
805-816.
Nepf, H. M. (1999). "Drag, turbulence, and diffusion in flow through emergent vegetation." Water
Resources Research 35(2): 479-489.
Nepf, H. M. and E. R. Vivoni (2000). "Flow structure in depth-limited, vegetated flow." Journal of
Geophysical Research-Oceans 105(CI2): 28547-28557.
Palmarsson, S. O. and S. G. Schladow (2008). "Exchange flow in a shallow lake embayment." Ecological
Applications 18(8): A89-A 106.
Palmer, MR, HM Nepf, TJ Pettersson, and JD Ackerman. 2004. Observations of particle capture on a
cylindrical collector: implications for particle accumulation and removal in aquatic systems.
Limnology and Oceanography, 49(1), 76-85.
Pfandl, K. and J. Boenigk (2006). "Stuck in the mud: suspended sediments as a key issue for survival of
chrysomonad flagellates." Aquatic Microbial Ecology 45(1): 89-99.
Purich, A. 2006. The Capture of Suspended Particles by Aquatic Vegetation. Env. Engineering Project
Dissertation, University of Western Australia, Perth, Australia.
11
Proposal: Tahoe Research Supported by SNPLMA 2010
V, Figures
:
u .. b
:
Figure 1. The capture efficiency 1] is defined as the ratio of the upstream width of streamlines for
which a particle traveling on will impact a vegetative surface to the width of a vegetative surface.
Clay water
r
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Arboretum water
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100
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Partlcle diameter [lJm)
Figure 2: Particle size distribution of the three main water types that were used in the preliminary
experiments. (Nover et aI., unpublished data).
12
Proposal: Tahoe Research Supported by SNPLMA 2010
Flow direction
Flume reservoir
Figure 3: The left panel shows the experimental setup with the flume, dowel array, placement of the
LISST-l OOX and the ADV as well as approximate water level. The right panel shows the dowel array
mounted on acrylic with approximate dimensions. (Nover et aI., unpublished data).
13
Proposal: Tahoe Research Supported by SNPLMA 2010
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Figure 4. Preliminary experiment results showing decline in volume concentration of fine particles
during two experiments with dowels (open symbols). The corresponding increase in light transmission is
shown by the two sets of data in the lower part of the figure. Both the particle concentration and the light
transmission are measured by the LISST. (Nover et aI., unpublished data).
14