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Massachusetts Stormwater Technology Evaluation Program Evaluating Stormwater BMPs Spring 2013. Constructed Wetlands. Removal Efficiency: 65-80% average 80% MassDEP TSS Removal Credit Key Features: Large area Peak flow control Biological treatment Maintenance: low to moderate
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Massachusetts Stormwater Technology Evaluation ProgramEvaluating Stormwater BMPsSpring 2013
Massachusetts Stormwater Technology Evaluation Project, UMass
Constructed Wetlands • Removal Efficiency: • 65-80% average • 80% MassDEP TSS Removal Credit • Key Features: • Large area • Peak flow control • Biological treatment • Maintenance: low to moderate • Cost: marginally higher than wet ponds http://www.txnpsbook.org, 2002 Source: MassDEP, 2008. Massachusetts Stormwater Handbook
Extended Detention Basins • TSS Removal Efficiency: • 60-80% average • 50% MassDEP TSS Removal Credit • Key Features: • Large area • Peak flow control • Maintenance: low • Cost: low to • moderate Source: MassDEP, 2008. Massachusetts Stormwater Handbook
Water Quality Swales • Removal Efficiency: • 65-805 average • 70% MassDEP TSS Removal Credit • Key Features: • Higher pollutant removal rates than drainage channels • Transport peak runoff and provide some infiltration • Maintenance: low to moderate • Cost: low to moderate http://www.txnpsbook.org, 2002 Source: MassDEP, 2008. Massachusetts Stormwater Handbook
Deep Sump Catch Basins • Removal Efficiency: • 9-35% average • 25% MassDEP TSS Removal Credit • Design Features: • Debris removal • Pretreatment • Maintenance: moderate to high • Cost: low to high Source: MassDEP, 2008. Massachusetts Stormwater Handbook
Innovative BMPs – Media Filtration • Removal Efficiency: • 50-80% average • Design rate: case by case evaluation • Design Features: • small area • Oil and Grease control • Maintenance: moderate • Cost: moderate Stormwater Management Inc, 2002 Massachusetts Stormwater Technology Evaluation Project, UMass
Innovative BMPs - Hydrodynamic • Removal Efficiency: • No treatment to 35% • Design rate: case by case evaluation • Design Features: • small area • Oil and Grease control • Maintenance: moderate • Cost: moderate Vortechs Inc, 2002
TARP- Technology Acceptance Reciprocity Program • Address technology review and approval barriers in policy and regulations; • Accept the performance tests and data from partner’s review to reduce subsequent review and approval time; • Use the Protocol for state-led initiatives, grants, and verification or certification programs; and • Share technology information with potential users in the public and private sectors using existing state supported programs CA IL MA MD NJ NY PA VA TX
Performance Verification - TARP • Storm Event Criteria to Sample • More than 0.1 inch of total rainfall. • A minimum inter-event period of 6 hours, where cessation of flow from the system begins the inter-event period. • Obtain flow-weighted composite samples covering a minimum of 70 % of the total storm flow, including as much of the first 20 % of the storm as possible. • A minimum of 10 water quality samples (i.e., 10 influent and 10 effluent samples) should be collected per storm event. • Determining a Representative Data Set • At least 50 % of the total annual rainfall must be sampled, for a minimum of 15 inches of precipitation and at least 15, but preferably 20, storms. Massachusetts Stormwater Technology Evaluation Project, UMass
Performance Verification - TARP • Stormwater Sampling Locations • Sampling locations for stormwater BMPs should be taken at inlet and outlet. • Sampling Methods • Programmable automatic flow samplers with continuous flow measurements should be used • Grab samples used for: pH, temperature, cyanide, total phenols, residual chlorine, oil and grease, total petroleum hydrocarbons (TPH), E coli, total coliform, fecal coliform and streptococci, and enterococci. • Stormwater Flow Measurement Methods • Primary and secondary flow measurement devices are required.
Is There Enough Data? Field Studies • 15+ storms • 15 inches of rainfall Lab Studies • 15 test runs
Are the Data Representative? • Weather conditions • Topography, land use • Soils, sediments
Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
Are the Data Representative?, Weather, Flows • Multiple samples per event • Field Studies: must include high flow/intensity storms • Consecutive storms • Sample all year • Lab Studies: Flow rates: 25%, 50%, 75%, 100%, 125%
Particle size: mean < 100 microns; distribution 55% sand, 40% silt, 5% clay Influent concentration 100 – 300 mg/l Are the Data Representative? Sediment
Are Results Accurate, Repeatable? • Quality Control tests, data • Standardized methods
Innovative BMPs - Advanced Sedimentation Rinker Inc, 2002
15 storm events 15 inches rain. 50% annual average. Particle size: mean < 100 microns - distribution: 55% sand, 40% silt, 5% clay Influent concentration: 100 – 300 mg/l Flows: range, up to 125% design capacity. Scour tests Summary – what to look for
Massachusetts Stormwater Technology Evaluation Project, UMass
BMPPerformance Comparison Table Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
Massachusetts Stormwater Technology Evaluation Project, UMass
MASTEP Rating System Category 0: MASTEP has not yet reviewed performance data for this technology. Category 1: TARP-compliant field study or equivalent lab study data available for this product Cat. 2: Sound field or lab study data available – some caveats Cat. 3: Data of moderate scientific validity exists – significant caveats Cat. 4: Reliable performance lacking
Higher rating does NOT mean better performance MASTEP evaluates quality ofperformance DATA NOT BMP Performance Results