Quantifying the benefits of urban stormwater management
SNPLMA Research Proposal: Round 11
Theme 2. Water Quality: Subtheme 2B.
October 27, 2010
Principal Investigator:
Research Collaborators:
Nicole Beck, PhD, 2NDNATURE LLC; nicole@2ndnaturellc.com
Brent Wolfe, PE, Northwest Hydraulic Consultants; bwolfe@nhcweb.com
Jeremy Sokusky, PE, Environmental Incentives; jsokulsky@enviroincentives.com
Agency Collaborators:
Kris Klein, Washoe County Public Works Division; KKlein@washoecounty.us
Robert Erlich, City of South Lake Tahoe Public Works Department; rerlich@cityofslt.us
Grant Contact:
Krista McDonald, 2NDNATURE LLC, krista@2ndnaturellc.com p. 831.426.9119
Total Funding Requested: $349,044.19
Total Cost Share: $65,000 - 90,000
HYPOTHETICAL URBAN CATCHMENT WASHOE COUNTY
Image courtesy of Google Earth
2009
500 Seabright Ave, Suite 205
Santa Cruz, California 95062
p 831.426.9119
f 831.426.7092
w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 1 II. PROPOSAL NARRATIVE A. PROJECT ABSTRACT This research will integrate a number of reliable and cost‐effective stormwater monitoring techniques (2NDNATURE and nhc 2010a, 2NDNATURE and nhc 2010b, 2NDNATURE et al. 2010a) with existing stormwater management tools1 customized for the Tahoe Basin Total Maximum Daily Load (TMDL) program (LRWQCB and NDEP 2010) to directly improve our quantitative estimates of the water quality benefits of key urban stormwater management practices. The research will focus on two priority research and management objectives: 1. Provide the first set of comprehensive data to validate Pollutant Load Reduction Model (PLRM) catchment‐scale estimates of pollutant loading and runoff using observed water quality and hydrologic data; and 2. Quantify the effectiveness and feasibility of improved road maintenance practices to reduce urban catchment pollutant loads. To address research objective #1, two urban catchments will be selected and monitored over the entire 2012 water year. The catchment land use and Treatment BMPs will be mapped and condition2 evaluated periodically throughout the 2012 water year. PLRM models of each catchment will be developed using catchment conditions and site specific meteorology. The urban catchment scale research is critical to validate how well our pollutant load estimation tools align with actual observed water quality loading and continue to validate priority hypotheses. The catchment scale observations and protocols will be developed in a manner that could be adopted and continued as a long‐
term monitoring effort under the Regional Stormwater Monitoring Program (RSWMP) to provide status and trend data on urban stormwater pollutant loading and effectively refine the supporting stormwater tools. To address research objective #2, the research team will work directly with two jurisdictions responsible for maintenance of roads: the City of South Lake Tahoe (CSLT) and Washoe County. Within each monitored catchment a range of road maintenance practices will be developed, documented and implemented by the jurisdiction on the subject roads. The Road RAM tool and the previously defined controlled road experiments will be used to evaluate the condition of all roads within the catchments on regular intervals. The implementation of the Road RAM field observations combined with stormwater quality data over the 2012 water year will allow statistical and modeling analysis of the relative effectiveness of the road maintenance practices conducted. Cost of implementation of each road maintenance practice over the year will be included to provide both water quality improvement effectiveness and cost benefit comparisons of the various practices studied. B. JUSTIFICATION STATEMENT The PLRM is a stormwater pollutant load model that can be used to quantify the expected load reductions of pollutants of concern to Lake Tahoe as a result of water quality improvement actions on urban lands. The actual condition of stormwater infrastructure associated with estimated load reductions from the PLRM can be verified each year using two Rapid Assessment tools (BMP RAM 2NDNATURE et al. 2009 and Road RAM 2NDNATURE et al. 2010b). The condition of stormwater infrastructure and roads is known to vary temporally and these variations affect pollutant load generation and control. These stormwater management tools are critical components of the Lake Tahoe TMDL and are the means by which the benefits of urban stormwater management is and will continue to be quantified in the Tahoe Basin. This proposal directly addresses all of the research needs outlined in the SNPLMA Round 11 Theme 2b by constraining, sampling and modeling urban pollutant generation (particularly from roads) and stormwater treatment in two urban catchments while simultaneously quantifying water quality benefits, monitoring the condition of infrastructure, and critiquing the effectiveness and feasibility of various road maintenance practices for water quality improvement. The 2NDNATURE and NHC team are the lead developers of the PLRM and RAM tools and associated research approaches that are supporting the Lake Tahoe TMDL. The research team has developed, tested and implemented a number of cost‐effective urban land use, stormwater and 1
Tahoe Basin stormwater tools that support the Lake Clarity Crediting Program and associated Lake Tahoe TMDL include: the Pollutant Load Reduction Model (PLRM) (NHC et al. 2009), the Road Rapid Assessment Methodology (Road RAM; 2NDNATURE et al. 2010b) and the Treatment BMP Maintenance Rapid Assessment Methodology (BMP RAM; 2NDNATURE et al. 2009).
2
Condition is defined as the surface and/or BMP state with respect to downslope water quality risk. An urban road with a poor condition is a high water quality risk downslope during a subsequent runoff event (NHC et al. 2009). A treatment BMP (i.e., dry basin or treatment vault) in poor condition is determined to be incapable of providing the intended water quality benefit during a subsequent runoff event and in need of maintenance to restore water quality performance to an acceptable level (2NDNATURE et al. 2009).
2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 2 treatment BMP water quality data collection techniques under previous contracts over the past few years (2NDNATURE 2008, 2NDNATURE and nhc 2010a, 2NDNATURE and nhc 2010b). The research proposed here would augment and expand upon previous research and data collection efforts to test hypotheses generated from the results of past research and prioritize future improvements of the tools being used to quantify feasible water quality improvements. Proposed data collection methods will combine a portable rain simulator, passive samplers and high resolution automated sampling to characterize urban catchments and treatment BMP water quality and hydrology. These water quality sampling techniques will be integrated with the existing RAM tools to test and validate the PLRM algorithms and empirical accuracy. The inclusion of the City of South Lake Tahoe and Washoe County jurisdictions on our research team will ensure a representative assessment of actual road maintenance actions to interpret observed land use and event‐based water quality and hydrologic data. Two urban catchments will be mapped in detail and instrumented with meteorological, water quality and continuous flow instrumentation to monitor stormwater runoff quality and pollutant loading. Land use and treatment BMP condition will be tracked over time and used to align PLRM model inputs to each monitored catchment. The location specific meteorological datasets will be loaded into the PLRM model and run to provide the predicted PLRM seasonal and water year hydrology and pollutant loading. The jurisdiction partners will supply maintenance information to the research team to provide a detailed chronicle of road maintenance practices and other water quality maintenance actions within the subject catchments. The PLRM predicted hydrology and pollutant loads will be compared to the observed hydrology and loads, providing an invaluable opportunity to test and validate the accuracy of the spatial catchment scale integration of land use distribution and conditions within PLRM. In addition, statistical evaluations will be conducted to identify correlations between observed road condition using Road RAM, the associated road maintenance strategy and other road attributes (road shoulder condition, road shoulder connectivity, road surface integrity, etc.) suspected to influence the condition of roads to test a number of hypotheses fundamental in the PLRM and Road RAM tools. This proposed research not only has very strong scientific relevance and will directly address the specific research needs outlined in the SNPLMA Round 11 subtheme 2b, but the process and associated findings will directly inform a number of assumptions and concepts outlined in the September 2009 version of the Lake Clarity Crediting Program (LRWQCB and NDEP 2009), the management strategy to achieve the TMDL goals and restore the clarity of Lake Tahoe. C. CONCISE BACKGROUND AND PROBLEM STATEMENT Problem statement: High resolution data is necessary to validate and refine the PLRM quantification of the benefits of stormwater management. PLRM estimates of pollutant loading are designed to be very sensitive to road condition, where road condition can be directly improved by effective road maintenance practices. Research is needed to verify these assumptions and quantify the pollutant load reductions on both a land use (roads) and urban catchment scale to assess effectiveness of road maintenance practices. Research is also needed to define the most efficient means to use observed urban stormwater hydrology and water quality data to validate and improve our confidence in a non‐processed based model such as PLRM. Background: The Crediting Program (LRWQCB and NDEP 2009) recommends the use of PLRM, Road RAM and BMP RAM by local jurisdictions and regulators to estimate and track urban load reductions over time. The Crediting Program directs urban jurisdictions to estimate annual load reductions using distinct urban catchments to preserve the physical mass balance concept that annual pollutant loading to Lake Tahoe is the sum of distinct input points (i.e., urban catchment outlets). PLRM is the most applicable stormwater model that can be used in the Tahoe Basin to estimate catchment load reductions as a result of water quality improvement actions on an average annual basis. The Road RAM and BMP RAM tools are used to assess the actual condition of urban lands and treatment BMPs over time and are expected to be validations of PLRM estimates, but continued research is needed to provide confidence in the alignment. The initial version of PLRM was developed using available empirical water quality data from Lake Tahoe stormwater monitoring as applicable. However, in most monitoring studies upon which the PLRM relies, many of the variables assumed to influence variability of catchment water quality were not 2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 3 observed or recorded. Now that some of the primary assumptions influencing pollutant loading are clearly designed into the PLRM, Road RAM and BMP RAM, focused water quality monitoring on an urban catchment scale for one complete water year coupled with detailed tracking and assessment of road maintenance practices will provide critical data to validate urban stormwater pollutant loading and the tools used to assess the loading. The 2NDNATURE team is currently completing a Round 9 SNPLMA grant to expand the existing dataset and refine the specific water quality parameters used within PLRM and the final technical document is expected to be completed in Fall 2011 (2NDNATURE and nhc, 2011). Specifically the research will result in potential recommended revisions of PLRM water quality parameters: 1. PLRM characteristic runoff concentrations (CRCs) used for specific land uses and associated conditions based on land use specific water quality sampling; and 2. PLRM characteristic effluent concentrations (CECs) expected at the outlet of specific treatment BMP types based on treatment BMP specific sampling of treated outflows (NHC et al. 2009). The 2NDNATURE team has also recently obtained a small instrumentation and protocol development contract from the Army Corps of Engineers (ACOE) for urban catchment scale monitoring and stormwater tool alignment (2NDNATURE et al. 2010a). The ACOE resources are extremely limited and will result in development of the protocols and monitoring strategy necessary to obtain continuous yet cost‐effective meteorologic, flow, and water quality data to comprehensively validate PLRM estimates and RAM outputs.The available ACOE resources will be used to instrument and monitor a single urban catchment for 3 months, including testing the feasibility of obtaining continuous turbidity measurements in a stormwater environment. The catchment scale protocols and logistical lessons learned using the ACOE funds will streamline the SNPLMA Round 11 effort and facilitate a full water year of data collection in two urban catchments. Tight collaboration and efficient information sharing with jurisdictional partners is critical to properly interpret urban catchment water quality data and the influence of land use and Treatment BMP maintenance practices there in. The 2NDNATURE team has a strong and continued working relationship with the CSLT and Washoe County stormwater managers and we have their continued commitment to maintain and provide the necessary detailed land use maintenance practice records. The urban catchment study design and jurisdictional collaboration will significantly increase our understanding of the sensitivity of pollutant loading to key load reduction opportunities in urban catchments, such as road maintenance practices and treatment BMP design. D. GOALS, OBJECTIVES, AND HYPOTHESES TO BE TESTED Hypothesis: The quantification of the benefits of stormwater management practices is reasonably modeled on an average annual basis by PLRM and tracked over time using customized RAM tools. Goal: This research will provide the first dataset to validate the critical tool hypotheses by providing a controlled urban catchment study that strategically characterizes the actual road maintenance practices and measures observed land use and catchment conditions, flow and water quality loading. Objectives: 1. Improve our understanding of the factors influencing pollutant loading from urban catchments and temporal variation associated with hydrologic, land use, and treatment BMP conditions. 2. Provide scientifically valid and reliable data that quantifies the effectiveness of road maintenance practices in the Tahoe Basin, including an assessment of cost‐effectiveness.
3. Working with local jurisdictional partners (CSLT and Washoe County), document relevant aspects of road and treatment BMP maintenance actions to better assess their relationship to monitoring data and modeling results. 4. Strategically instrument catchments to collect high resolution water quality data to characterize catchment loading and treatment BMP performance, and test these against pollutant loading estimates generated using the current stormwater tools for the TMDL program. 5. Conduct modified PLRM simulations on event, seasonal and annual scales and compare to monitoring information to investigate the effectiveness of PLRM algorithms for integrating pollutant generation and treatment BMP performance as average annual loads. If warranted, develop recommendations for improving PLRM based on observed catchment scale hydrology and water quality. 6. Statistically evaluate the sensitivity of key factors expected to influence catchment water quality. Key factors may include seasonal and event meteorologic characteristics, road maintenance practices, road 2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 4 attributes, catchment land use distribution, road condition, treatment BMP design parameters, treatment BMP condition, maintenance practices, etc. E. APPROACH, METHODOLOGY AND LOCATION OF RESEARCH Location of research The exact location of this research will be defined in collaboration with CSLT and Washoe County. One catchment will be located within CSLT and one catchment will be located within Washoe County in the Tahoe Basin. Approach Catchment pollutant loads are the integrated signal of pollutant sources and stormwater volumes within the catchment. The PLRM and Road RAM are based on the primary assumption that not all surfaces of the same land use type will have the same influence on water quality downslope. In other words, both the land use type (primary road, secondary road, single family residential, commercial/institutional, etc.) and the condition (poor, degraded, fair, acceptable, or desired) influence measured water quality. Key factors believed to have the most significant effect on water quality (road maintenance practices, treatment BMP maintenance, impervious area connectivity, etc.) are defined in the TMDL stormwater tools and used as inputs for pollutant load modeling. In order to better constrain the variability of water quality data obtained from an urban catchment the dataset should be analyzed considering physical and geographic factors of the catchment (such as slope, directly connected impervious area, size, etc.) as well as land use type, distribution and condition. Existing research continues to indicate that the greatest achievable urban water quality improvements can be accomplished with improved road maintenance strategies (2NDNATURE et al. 2010a, 2NDNATURE et al. 2011, 2NDNATURE and nhc 2010a, 2NDNATURE et al. 2010b). Roads are assumed to be a significant source of the pollutants of concern, particularly TSS and FSP generated from road abrasive applications, erosion of unprotected road shoulders and an increase in the fine sediment particle (FSP) fraction due to pulverization by vehicular traffic. Roads are also a primary transport pathway for stormwater runoff. Even in mixed land use catchments, the road network often comprises the majority of directly connected impervious area (DCIA) and routes the majority of stormwater through urban areas to receiving waters. Over the past 5 years the 2NDNATURE team has focused on developing, testing and implementing stormwater data collection protocols that constrain the specific land use conditions and relative pollutant sources using scientifically defensible, yet cost‐effective techniques (2NDNATURE 2006, 2NDNATURE 2008, 2NDNATURE 2010a, 2NDNATURE 2010b, 2NDNATURE et al. 2010). The land use and treatment BMP specific techniques and protocols will be will be included as part of the initial catchment integration protocol development (2NDNATURE et al. 2010a) to provide a monitoring program specifically designed for comparison with PLRM pollutant load predictions for the selected urban catchments. For the purpose of making this comparison, PLRM will be modified and run on event and seasonal time scales. PLRM model developers are on the research team and will be involved in these comparisons to ensure that short term data are interpreted correctly in the context of long term annual average load predictions from PLRM. Figure 1 summarizes the catchment integration of the proposed data collection and modeling efforts proposed by this research. Controlled road experiments on Tahoe Basin roads have indicated that road condition is most sensitive to road maintenance practices, particularly during winter and early spring when road conditions are documented to be at the greatest annual water risk (2NDNATURE et al. 2010b). The 2NDNATURE research team will work collaboratively with the jurisdiction partners to define, characterize and track the specific range of road maintenance practices that will be included in the research and the correlation between road maintenance practices, road condition and catchment water quality will be tested (Figure 2). Methodology Catchment pollutant generation Building upon the existing research, protocol development and datasets, the 2NDNATURE team proposes to integrate the previously developed and tested source control and treatment evaluation techniques into the catchment scale to compare to PLRM predictions. Varying levels of road maintenance actions will be defined and collaboratively implemented with two local jurisdictions (City of South Lake Tahoe and Washoe County) within the catchments of interest for the 2012 water year. Each catchment will be identified and all infrastructure and key features; such as stormwater flow path boundaries, road attributes, land use conditions, treatment BMPs, etc will 2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 5 be mapped and field verified. Each urban catchment will be strategically instrumented to provide meteorology, continuous flow, continuous turbidity and targeted water quality sampling at priority locations. Road and treatment BMP conditions will be monitored throughout the water year, targeting evaluations prior to targeted runoff events. Discrete water quality samples at the outlet of the catchment will be obtained to represent a range of runoff event types (winter rain, rain on snow, summer thunderstorm and snowmelt) within each catchment. The continuous hydrologic and turbidity record will allow the research team to extrapolate the pollutant loads for sampled events and to reasonably estimate seasonal and annual pollutant loading. The pollutants of concern3 for this research are fine sediment particles (FSP; < 16um), total suspended sediment (TSS), total phosphorous (TP) and the biologically available, soluble reactive phosphorous (SRP). Figure 1 illustrates the proposed spatial catchment instrumentation and data collection strategy. The catchment scale observations and protocols will be developed in a manner that could be adopted and continued as a long‐term monitoring effort under RSWMP to provide status and trend data on urban stormwater pollutant loading. Treatment BMP performance Each of the urban catchments selected will include a number of distributed treatment BMPs in the catchment as well as a centralized treatment BMP at the outlet (see Figure 1). The treatment BMPs within each selected catchment will be mapped, characterized by type, and key design parameters will be documented. Complete BMP RAM evaluations (2NDNATURE 2009) will be conducted prior to targeted storm events to define and track treatment BMP condition to compare to water quality performance. The inlet to the centralized treatment BMPs will be instrumented to obtain continuous flow and turbidity measurements per protocols developed by 2NDNATURE and nhc 2010a. Stage recorders will be installed in the centralized treatment BMPs and surveyed to ensure accurate continuous water budgets are created. The inlet will also serve as the catchment outlet water quality monitoring point, informing the catchment pollutant generation analysis above. The inlet and outlet of the centralized treatment BMP will be instrumented with passive sampling devices set at strategic elevations to cost‐
effectively capture effluent concentrations over time (2NDNATURE and nhc 2010a). The integrated catchment evaluation approach will increase our understanding of how specific treatment BMP design parameters, inflowing loads, seasonality and treatment BMP condition affect resultant effluent concentrations from specific treatment BMP types, and how these should be integrated to provide characteristic effluent concentrations (CECs) in PLRM. Modified PLRM models will be produced for each centralized treatment BMP and simulations will be used to test sensitivity of treatment BMP performance to each of these factors and to compare to observed performance. These simulations will be used to investigate the effectiveness of current PLRM algorithms to estimate annual average loads using CECs. Road maintenance practice effectiveness An experimental design (summarized in Figure 2) will be developed to adequately quantify the effectiveness and feasibility of specific road maintenance practices to improve urban water quality. Within each monitored catchment a range of road maintenance practices will be developed, documented and implemented by the jurisdiction on the subject roads. Key components of road maintenance practices include spatially explicit records of the amount, frequency and type of abrasives applied, sweeping frequencies and the type of sweeper used and other actions expected to reduce pollutants available on the road surface (i.e. snow haul). All road maintenance practices will be documented in detail and each type of abrasive used on any roads monitored will be collected and analyzed (pre‐application) for geochemical and grain size characteristics by the research team. A range of road maintenance strategies will be defined and implemented within the catchments that are expected to yield both good and poor road conditions in order to test the hypotheses and quantify the effectiveness of specific strategies. Cost of implementation of each road maintenance practice over the year will be included to provide both water quality and cost benefit comparisons of the various strategies studied. Using GIS spatial tools, the specific road 3
All water samples collected for submission to the DRI analytical laboratory will be analyzed for the following pollutants of concern: total suspended sediment (TSS); particle size distribution (PSD) for the following size fractions, 1µm, 5 µm, 10 µm, 16 µm, 63 µm, 100 µm, and 1000 µm; turbidity; total phosphorous (TP); dissolved phosphorous (DP); and soluble reactive phosphorous (SRP). Coordination with DRI researchers will allow subsequent particle count analysis as well as all other sample details, thereby contributing to the urban particle number, FSP concentration by mass, and turbidity regression equation development. 2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 6 segments treated with each specific road maintenance strategy over the water year will be mapped by Road Class (Figure 2). The frequency of each road treatment will be chronicled in detail by the jurisdiction partner maintaining date specific records of what and when abrasives are applied or sweeping is conducted. This collaborative effort for documenting road maintenance strategies in an efficient and accurate manner will be a benefit that can be shared with other Tahoe Basin jurisdictions. The research team will inventory all road attributes that may also influence the condition of roads for pollutant generation (i.e., road surface integrity, traffic density, slope, road shoulder connectivity, road shoulder condition, etc.) in each catchment per Road RAM protocols (2NDNATURE et al. 2010b). The Road RAM field evaluations (STEP 4B) will be implemented on regular intervals to evaluate the condition of all roads within the catchments. Controlled road sampling experiments previously developed (2NDNATURE and nhc 2010a, 2NDNATURE et al. 2010b) will be implemented simultaneously on discrete road segments to continue to verify Road RAM observations with quantitative FSP CRC data. The implementation of the Road RAM field observations combined with stormwater quality data over the 2012 water year will allow a statistical analysis of the relative effectiveness of the road maintenance practices conducted and the correlations of these practices on observed catchment water quality. Catchment data analysis power The experimental design of this research will provide data to conduct a sensitivity analysis of the catchment water quality signal to respective road maintenance practices and associated road conditions. Knowing that road condition varies seasonally due to significant shifts in anthropogenic sources and both natural and anthropogenic sinks of pollutants on roads, statistical sensitivity analyses can be conducted to evaluate the influence road conditions have on catchment water quality. The detailed records of the specific road maintenance practices implemented over the same time frames will allow powerful evaluations of how road maintenance practices can improve urban catchment pollutant loading. This proposed Round 11 research will test the PLRM land use pollutant generation and transport algorithms by mapping, tracking and evaluating the distribution of land uses and associated conditions within these urban catchments. The event specific meteorology and land use condition observations will be loaded into the catchment specific PLRM models to create event based PLRM model estimates and compare to measured values. PLRM estimates are conducted on an average annual basis over an 18‐yr simulation; however PLRM can be run using a single water year’s meteorologic data. The catchment condition, water quality and treatment BMP condition dataset over a complete water year will provide the first real datasets necessary to validate PLRM predictions. Modified PLRM models will be created for both catchments and model simulations will be conducted on selected event, seasonal and annual time scales. Deviations between predicted and observed pollutant loads will be investigated using sensitivity analyses to identify potential improvements to PLRM algorithms. The results of the simulations will be used to investigate the predictive power of using land use conditions in PLRM and to evaluate the effectiveness of current algorithms using Characteristic Runoff Concentrations (CRCs) to estimate average annual pollutant loads. The continuous annual catchment hydrology and observed event specific loads will be used to formulate a scaling approach to estimate annual catchment loading based on a select number of discrete monitored events. The scaling technique will be extremely useful to advise jurisdictions and RSWMP on how to design event monitoring data collection and analysis for use in future validation of annual average loading estimates from PLRM. F. RELATIONSHIP OF THE RESEARCH TO PREVIOUS AND CURRENT RELEVANT RESEARCH, MONITORING, AND/OR ENVIRONMENTAL IMPROVEMENT EFFORTS The proposed research will inform and/or build upon the following Tahoe Basin efforts: • Lake Tahoe Total Daily Maximum Load (TMDL) • Lake Clarity Crediting Program (Crediting Program) • Lake Tahoe TMDL Accounting and Tracking Database (Tracking Tool) • Pollutant Load Reduction Model (PLRM) • Best Management Practices Maintenance Rapid Assessment Methodology (BMP RAM) 2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 7 •
•
•
Road Rapid Assessment Methodology (Road RAM) Tahoe Stormwater and BMP Performance Database Regional Stormwater Monitoring Program (RSWMP) G. STRATEGY FOR ENGAGING WITH MANAGERS AND OBTAINING PERMITS The CSLT and Washoe County Public Works Departments are direct partners in this research and all coordination of work and instrumentation permits on their lands will be completed directly. The jurisdiction personnel will collaborate with the research team during catchment assessments and maintenance operations. The jurisdictions will supply detailed records, per information management protocols agreed upon by the team, for water quality maintenance actions. Team meetings and information sharing will continue throughout the research. Regulators, RSWMP developers and interested urban jurisdictions will be engaged in the form of a Technical Advisory Committee (TAC) to provide feedback on the draft Technical Report prior to the submission of the Final Document. H. DESCRIPTION OF DELIVERABLES/PRODUCTS AND PLAN FOR HOW DATA AND PRODUCTS WILL BE REVIEWED AND MADE AVAILABLE TO END USERS Task 1. Catchment selection, monitoring plan and PLRM model development Sampling instrumentation will be purchased, constructed, and installed according to the protocols outlined in a Monitoring Plan. The Monitoring Plan will incorporate the lessons learned from the urban catchment scale monitoring and stormwater tool alignment project (2NDNATURE et al. 2010a). The PLRM models for each selected catchment will be created to allow event specific inputs including event hydrology, land use condition and treatment BMP condition documented prior to the event occurrence. Task 2. Road maintenance strategy documentation The research team and jurisdiction partners will conduct a series of collaborative meetings to collectively document the specific road maintenance practices implemented on the catchment roads over the 2012 water year. Task 2 will include detailed maps of strategy routes and associated practices to be implemented. A record management approach will be developed to best maintain frequency of actions and easily provide chronology of actions both spatially and temporally to the research team. The detailed strategies and implementation recording methods will be documented and shared with other stormwater managers and regulators. Task 3. Catchment and event monitoring and data collection All information and data collection will be conducted per documented protocols. Catchment, road and treatment BMPs conditions will be evaluated and documented on regular intervals and prior to targeted runoff events. All hydrologic and water quality data collection sites will be maintained to provide continuous and discrete sampling to achieve project goals over the complete 2012 water year. Task 4. Data management and analysis; PLRM simulations and hypothesis testing All data will be QA/QC’d immediately following collection and entered into an MS Access database for efficient storage and simple extraction following 2NDNATURE data collection protocols. BMP RAM and Road RAM data management will be conducted within the respective tool databases. Data analysis and PLRM simulations will be ongoing as new data is obtained. The detailed analysis will focus upon hypothesis testing of specific questions of the PLRM, Road RAM, and BMP RAM and how the integration of these tools as well as actual road maintenance practices relate to observed catchment pollutant loadings. The analysis will focus upon clear guidance on the linkage between the TMDL Program annual average catchment loading estimates and event specific land use conditions, treatment BMP conditions and catchment loads that can be directly measured. The results of the analyses will be presented in Task 5 deliverables. Task 5. Technical reporting Quarterly SNPLMA progress reports will provide updates on research progress quarterly. The research team will compile the Draft Technical Report for TAC review and comment, which will be incorporated into the Final Technical Report that will include detailed methods, findings, and recommendations for specific tool improvements. The Technical Report will also include a quantification of road maintenance practice effectiveness as well as cost‐effective analyses of each strategy. 2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 8 III. SCHEDULE OF MAJOR MILESTONES/DELIVERABLES Project schedule provided below is based on contract award in July 2011. Task Task 1. Catchment selection, Monitoring plan and PLRM model development Task 2. Road Maintenance Strategy Task 2.1 Road maintenance strategy development with jurisdiction partners Task 2.2 Road maintenance strategy and reporting summary Task 3. Catchment and event monitoring and data collection Task 4. Data management and analysis; PLRM simulations and hypothesis testing Task 5. Technical Reporting Task 5.1 Quarterly SNPLMA progress reports Task 5.2 Draft Technical Report Task 5.3 TAC meeting, comments and feedback Task 5.4 Final Technical Report Start Month End Month July 2011 Sept 2011 July 2011 July 2011 Oct 1 2011 Sept 2011 Nov 2011 Sept 30 2012 Oct 2011 Jan 2013 Completed and submitted to USFS quarterly; Jan 1, April 1 July 1, Oct 1. Oct 2011 Mar 2013 Mar 2013 May 2013 2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
Proposal: Tahoe Research Supported by SNPLMA Round 11 Theme 2b: Quantifying the benefits of urban stormwater management p. 9 IV. LITERATURE CITED/REFERENCES 2NDNATURE. 2006. Detention Basin Treatment of Hydrocarbon Compounds in Urban Stormwater. Final Technical Report. Prepared for South Lake Tahoe Public Utility District. March 2006. ftp://www.2ndnaturellc.com/2ndnature/2NDNATURE_Reports/Lake%20Tahoe/Detention%20Basin%20Treatment
%20of%20Hydrocarbon%20Compounds%20in%20Urban%20Stormwater%202006.pdf 2NDNATURE. 2008. Water Quality Performance Evaluation of Park Avenue Detention Basins; South Lake Tahoe, CA. Final Technical Report. Prepared for City of South Lake Tahoe Engineering Division. August 2008. ftp://www.2ndnaturellc.com/2ndnature/2NDNATURE_Reports/Lake%20Tahoe/Water%20Quality%20Performance
%20Evaluations%20of%20Park%20Ave%20Detention%20Basins%202008.pdf 2NDNATURE and Northwest Hydraulic Consultants (nhc). 2010a. PLRM, Focused Stormwater Monitoring to Validate Water Quality Source Control and Treatment Assumptions. Final Technical Report. Prepared for US Army Corps of Engineers, Sacramento District. March 2010. ftp://2ndnaturellc.com/2ndnature/2NDNATURE_Reports/Lake%20Tahoe/PLRM%20Refinement_FinalPhaseI_Tech
nicalReport.pdf 2NDNATURE and nhc. 2010b. PLRM Refinement Monitoring: Phase II. Final Monitoring Plan. Prepared for USFS Lake Tahoe Basin Management Unit. July 2010. ftp://2ndnaturellc.com/2ndnature/2NDNATURE_Reports/Lake%20Tahoe/PLRMRefinement_FinalPhaseII_Monitori
ngPlan.pdf 2NDNATURE and nhc. 2011. PLRM Refinement Monitoring: Phase II. Final Technical Report. Prepared for USFS Lake Tahoe Basin Management Unit. Expected December 2011. 2NDNATURE, nhc and Environmental Incentives (EI). 2009. BMP Maintenance Rapid Assessment Methodology (BMP RAM) Technical Document and Users Manual. Lake Tahoe, CA. Prepared for the Army Corps of Engineers. September, 2009 http://www.swrcb.ca.gov/rwqcb6/water_issues/programs/tmdl/lake_tahoe/ 2NDNATURE, nhc, and EI. 2010a. Pilot catchment scale testing and protocol development of Lake Tahoe stormwater tools. Funded by the Army Corps of Engineers. Contract awarded September 2010, expected completion September 2011. 2NDNATURE, nhc and EI. 2010b. Road Rapid Assessment Methodology (Road RAM) Technical Document and Users Manual, Tahoe Basin. Prepared for the California Tahoe Conservancy and Nevada Division of Environmental Protection. Expected November 2010. 2NDNATURE, nhc, and EI 2011. Placer County Stormwater TMDL Strategy. Final Technical Report. Prepared for Army Corps of Engineers and Placer County. Expected March 2011 US Army Corps of Engineers (ACOE). 2009. Lake Tahoe TMDL Tracking Tool is the accounting database tool used by urban jurisdictions and program managers to submit, approve and track catchment load reductions and associated credit schedules. Version 1 of the TMDL Tracking Tool was released by 2NDNATURE and Environmental Incentives in October 2009 and funded by the Army Corps of Engineers. Lahontan Regional Water Quality Control Board (LRWQCB) and Nevada Division of Environmental Protection (NDEP). 2009. Lake Clarity Crediting Program Handbook. Developed by Environmental Incentives. September 2009. http://www.swrcb.ca.gov/rwqcb6/water_issues/programs/tmdl/lake_tahoe/index.shtml LRWQCB and NDEP. 2010. Tahoe Basin Total Maximum Daily Load, Technical Report. California and Nevada. June 2010. http://www.swrcb.ca.gov/rwqcb6/water_issues/programs/tmdl/lake_tahoe/index.shtml 2NDNATURE, LLC
500 Seabright Avenue Suite 205 Santa Cruz CA 95062 p 831.426.9119 w 2ndnaturellc.com
CONTROLLED ROAD EXPERIMENTS
Land use pollutant generation and transport
Roadside sampling techniques used to quantify urban
land use CRCs. (2NDNATURE and nhc 2010a)
Road RAM evaluates the relative condition of an road segment using verified
visual proxies and detailed protocols.
(2NDNATURE et al. 2010b)
SECONDARY ROAD
URBAN
CATCHMENT
BOUNDARY
The portable rainfall simulator applies
a standardized volume of water at a
constant intensity and rate. The portable simulator facilitates the repeatable collection of 1 L of water applied
to a 1 sq ft of surface.
COON ST
FOX ST
CUT THROAT AVE
LOCH LEVON AVE
SINGLE FAMILY RESIDENTIAL
(SFR) PARCEL
TREATMENT BMP
CATCHMENT
GOLDEN AVE
DRY BASIN
BMP RAM used to evaluate
the condition of treatment
BMP. (2NDNATURE et al.
2009)
INLET
OUTLET
NOR
LAKE TAHOE
Stormwater Treatment
Automated and/or passive sampling techniques used
to characterize water quality at inlet and outlet of
Treatment BMP. Continuous water budget obtained
using continuous stage
recorders and topo survey
of BMP. (2NDNATURE and
nhc 2010a)
TH L
AKE
BLV
D (H
WY
SALMON AVE
28)
COMMERCIAL (CICU) PARCEL
Passive samplers used to
sample CECs of Treatment
BMPs.
URBAN CATCHMENT OUTLET
PLRM estimates validated using catchment
observed hydrology and pollutant loading.
(nhc et al. 2009)
*Coon Catchment and Treatment BMP Catchment are drawn for illustrative purposes only.
INTEGRATION OF STORMWATER TOOLS IN AN URBAN CATCHMENT
FIGURE 1
TESTING CORRELATIONS BETWEEN ROAD MAINTENANCE PRACTICE EFFECTIVENESS
AND OBSERVED CATCHMENT WATER QUALITY
CONTROLLED ROAD
EXPERIMENTS
validates1
ROAD RAM
1
measures
measures
SPECIFIC ROAD SITES
(termed Road Segments)
Controlled experiments will be
conducted concurrently with Road
RAM observations to continue to
validate Road RAM results.
ROAD CONDITION
SPATIAL SCALE
CATCHMENT AND/OR
JURISDICTION WIDE
CATCHMENT ROAD
NETWORK CONDITION
correlates to4
correlates to3
2
Road maintenance practices
performed in the selected catchments (CSLT and Washoe County) will be defined by practices
and ranked by the expected
relative water quality impacts
based on the net sources and
sinks of pollutants for each
practice. Road class simplifies
spatial and temporal tracking
of the actual road maintenance
practices performed on specific
road segments.
ROAD CLASS
spatially
mapped
URBAN
CATCHMENT
WATER QUALITY/
POLLUTANT LOADING
grouped by2
ROAD MAINTENANCE
PRACTICES
3
Frequent measures of road condition will be
compared to the respective road maintenance
practices performed as documented by the
jurisdictional partners. This research will provide
the first Tahoe specific analysis of road maintenance practice effectiveness.
4
Road RAM allows the spatial integration of discrete
road segment observations to estimate the urban
catchment road network condition. This research will
provide event, seasonal and annual documentation of
catchment road condition. Simultaneous catchment
water quality and pollutant loading over the same time
scales will provide scientifically defensible data to test
the correlation between road condition and catchment
water quality as measured at catchment outfall.
PROPOSED HYPOTHESIS TESTING
FIGURE 2