USDA Forest Service

Pacific Southwest Research Station


Pacific Southwest Research Station
800 Buchanan Street
Albany, CA 94710-0011

(510) 559-6300

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Priority Urban Stormwater Monitoring to Directly Inform the Pollutant Load Reduction Model (PLRM)

Full title: Priority urban stormwater monitoring to directly inform the Pollutant Load Reduction Model (PLRM)


Lead Researchers: Nicole Beck, 2nd Nature LLC


The initial version of the Pollutant Load Reduction Model (PLRM) is currently in development by northwest hydraulic consultants (nhc), 2NDNATURE, and Geosyntec Consultants through grants provided by the US Army Corps of Engineers (USACE) and the Nevada Department of Environmental Protection (NDEP). The objective of the PLRM is to provide Lake Tahoe resource managers with a tool to evaluate pollutant load reduction alternatives for urban storm water quality improvement projects. The research team submitting this proposal is the PLRM development team and the SNPLMA research results will directly improve confidence in PLRM loading estimates, particularly for very fine sediment loads for Lake Tahoe urban areas. The PLRM estimates pollutant loads using two primary water quality functions, Characteristic Runoff Concentrations (CRCs) and Characteristic Effluent Concentrations (CECs). A CRC is a representative concentration for a pollutant of concern in runoff from a specific urban land use and associated condition. A CEC is a representative effluent concentration for a pollutant of concern from a specific storm water treatment BMP type (SWT). When combined with continuous runoff hydrology from the PLRM, CRCs and CECs provide a representative estimate of average annual pollutant loading and a relative comparison of average annual pollutant loading among alternatives. The greatest limitation in the initial version of the PLRM (expected to be released in early 2009) is the lack of very fine sediment data (<20 microns) to inform CRCs and CECs. The funding for research in this proposal will be highly cost effective by 1) building on the research team's experience with PLRM development, 2) building on previous analyses of existing data to create the PLRM CRC and CEC database, and 3) augmenting an initial phase of urban stormwater data collection to inform PLRM currently being initiated for the USACE (2008). The goals of this research are to 1) provide improved scientific basis to estimate pollutant CRCs (focusing on very fine sediment) and their variability with land use conditions and 2) estimate very fine sediment CECs for typical Lake Tahoe SWTs and their variability with fundamental design parameters. This research addresses two of the SNPLMA Water Quality subthemes (2A and 2B). The CRC research will address both Water Quality subthemes 2A and 2B and the CEC research will primarily address Water Quality subtheme 2A, all of which will directly inform PLRM data gaps.

Expected date of final products: February 2012.
Progress Report available for download

Schedule of milestones and deliverables

The project is expected to start in July 2009 and is scheduled to continue through February 2012.

Del # Task # Sub-
task #
Deliverable/Task Start Date End Date
1     Contract or Agreement May 2009 Jul 2009
a   PSW establishes agreement with 2ndNature    
b   2ndNature establishes subagreements with contractors    
2     Design Development/Refinement Jun 2009 Sep 2009
a   Revise and update the ACE Monitoring Plan, which constituted an initial phase of storm water data collection to fill critical PLRM data gaps Jun 1, 2009 Jul 31, 2009
b   Conduct and summarize PLRM advisory committee meeting   Jun 1, 2009 Aug 31, 2009
c   Revise and finalize Final Monitoring Plan   Sep 1, 2009 Sep 30, 2009
3     Inventory/assessment/monitoring of water quality Oct 2009 Jun 2011
a   Station implementation and maintenance    
1 Instrument stations   Oct 2009 Dec 2009
2 Maintain stations over course of project    Oct 2009 Jun 2011
b   Data Collection, Data Management and Data Analysis    
1 Collect controlled experiment data   Oct 2009 Jun 2011
2 Collect event‐based sampling data   Oct 2009 Jun 2011
3 Manage data Oct 2009 Jun 2011
4 Test, validate and refine Pollutant Load Reduction Model Oct 2009 Jun 2011
5 Analyze data Oct 2009 Jun 2011
4     Scientific reports, systems, or related products Jun 2009 Feb 2012
a   Draft and Final Technical Report    
1 Draft Technical Report and present to Technical Advisory Committee Jun 2011 Sep 2011
2 Present Draft Technical Report to PLRM Advisory Committee Oct 2011 Nov 2011
3 Produce Final Technical Report Dec 2011 Feb 2012
Last Modified: Mar 28, 2013 02:52:07 PM