stormwater management eric winkler, ph.d. and susan guswa, p.e. center for energy efficiency and...

Stormwater ManagementStormwater Management

Eric Winkler, Ph.D. and Susan Guswa, P.E.

Center for Energy Efficiency and Renewable EnergyUniversity of Massachusetts

Annual Conference onWatershed Conservation 2002

September 20, 2002Amherst, MA

www.ceere.org

Presentation OutlinePresentation Outline

Water Quantity and Quality Issues

Rules Today and Tomorrow

Structural and Non-Structural Controls

Metrics and Measures

SUMBER: www.mastep.net/documents/StormwaterMgt.ppt

Hydrologic CycleHydrologic Cycle

http://www.mde.state.md.us/environment/wma/stormwatermanual/

Inland Natural SystemsInland Natural Systems

Water Quantity Effects Water Quantity Effects

Increased flooding potential

Changes to streambed morphology

http://www.forester.net, 2002

Water Quantity Effects Water Quantity Effects

Decrease in base flows

Water Quality Effects Water Quality Effects Increased pollutant load

– Habitat degradation– Public health and recreation impacts

Sean Chamberlain, 2002

Water Quality Effects Water Quality Effects Nutrient and Sediment Transport

Stormwater Pollution SourcesStormwater Pollution Sources

Urban runoff Construction Agriculture Forestry Grazing Septic systems Recreational boating Habitat degradation Physical changes to stream channels

http://www.sierraclub.org/sprawl, 2002

Flood Control /ConveyanceFlood Control /Conveyance

http://www.nae.usace.army.mil/recreati/lvl, 2002

http://www.lawrenceks.org, 2002

Water Quality – Stormwater ConstituentsWater Quality – Stormwater Constituents

SedimentNutrients: nitrogen and

phosphorousOil, grease, and organic

chemicalsBacteria and virusesSaltMetals

http://www.txnpsbook.org, 2002

Stormwater ConstituentsMedian ConcentrationsStormwater ConstituentsMedian Concentrations

Constituent Units Urban Non-Urban

Total Suspended Solids (TSS) mg/l 67-101 70

Chemical Oxygen Demand (COD) mg/l 57-73 40

Total Phosphorous (P) mg/l 201-383 121

Total Kjeldahl Nitrogen mg/l 1179-1900 965

Nitrate + Nitrite mg/l 558-736 543

Lead mg/l 104-144 30

Copper mg/l 27-33 --

Zinc mg/l 135-226 195

Source: U.S. EPA, Nationwide Urban Runoff Program, 1983.

Stormwater Management ChallengesStormwater Management Challenges

Variability of Flows (Duration, Frequency, Intensity)

Difference between peak control and treatment objectives

Different water quality constituents require different treatment mechanisms

Site-to-site variability of quantity and quality Maintenance of non-centralized treatment units Monitoring and measurement

Treatment EventsTreatment Events Criteria for Storm Events

Boston Logan Rainfall Record 1920 - 1999Cumulative Rainfall Depth Percentage

0

10

20

30

40

50

60

70

80

90

100

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8

Rainfall Depth (in)

Pe

rce

nt

of

To

tal

Cu

mu

ltiv

e D

ep

th

Figure 6. Cumulative Rainfall record for Boston Logan 1920 - 1999.

Sizing SystemsSizing Systems Intensity / Duration Frequency Relation

Calculating Peak Runoff RatesCalculating Peak Runoff Rates

Rainfall Runoff Analysis /Rational Method

Qp = CiA

C = constant runoff coefficienti = rainfall intensityA = drainage area (tc = time of concentration < rainfall duration)

0

0.2

0.4

0.6

0.8

1

0 1 2 3 4 5 6

t / Tp

Q / Qp

Federal RegulationsFederal Regulations

1987 Clean Water Act Amendments (U.S. EPA)– 1990 Phase I National Pollutant Discharge

Elimination System (NPDES) Storm Water Program

– 1999 Phase II NPDES Storm Water Program 1990 Costal Zone Act Reauthorization

Amendments, Section 6217 (U.S. EPA / NOAA)– Costal Zone Management Program

NPDES Permit ProgramNPDES Permit Program

Goal: reduce negative impacts to water quality and aquatic habitat

Requirement: develop storm water pollution prevention plans (SWPPPs) or storm water management programs with minimum control measures

Implementation: use best management practices (BMPs)

NPDES ApplicabilityNPDES ApplicabilityPhase I

"Medium" and "large" municipal separate storm sewer systems (MS4s) located in incorporated places or counties with populations of 100,000 or more

Eleven categories of industrial activity, one of which is construction activity that disturbs five or more acres of land

Phase II Certain regulated small

municipal separate storm sewer systems (MS4s)

Construction activity disturbing between 1 and 5 acres of land (i.e., small construction activities)

Phase II Minimum Control MeasuresPhase II Minimum Control Measures

Public education and outreach on storm water impacts

Public involvement/participation Illicit discharge detection and elimination Construction site storm water runoff control Post-construction storm water management in new

development and redevelopment Pollution prevention/good housekeeping for municipal

operations

Website for EPA NPDES Phase II Fact Sheets: http://cfpub.epa.gov/npdes/stormwater/swfinal.cfm

Massachusetts RegulationsMassachusetts Regulations

Clean Waters Act Wetlands Protection Act Rivers Protection Act

1997 Stormwater Management Standards– Developed jointly by CZM and DEP– Federal permits need to meet Stormwater

Management Standards– Administered by DEP and Conservation

Commissions

Stormwater Management StandardsStormwater Management Standards

1. No new untreated storm water discharges allowed

2. Post-development peak flow discharge rates < pre-development peak rates

3. Minimize loss of recharge to groundwater

4. Remove 80% of average annual total suspended solids (TSS) load (post development)

5. Discharges from areas with higher potential pollutant loads require use of specific BMPs

Stormwater Management StandardsStormwater Management Standards

6. Storm water discharges to critical area require use of approved BMPs designed to treat 1 inch runoff volume (post development)

7. Redevelopment sites must meet the Standards

8. Construction sites must utilize sediment and erosion controls

9. Storm water systems must have an operation and management plan

Non-Structural BMPsNon-Structural BMPs Pollution prevention/source

control Street sweeping Storm water collection system

cleaning and maintenance Low impact development and

land use planning Snow and snowmelt

management Public Education

http://www.tennatoco.com/stormwater, 2002

Better DesignBetter Design Green roofs High Density Grassed/Porous Pavement

http://www.lrcusace.army.ml, 2002

Structural BMPsStructural BMPs

Detention/Retention and Vegetated Treatment: detention basins, wet retention ponds, constructed wetlands, water quality swales

Filtration: sand and organic filters

Advanced Sedimentation/Separation: hydrodynamic separators, oil and grit chamber

Infiltration: infiltration trenches, infiltration basins, dry wells (rooftop infiltration)

Pretreatment: water quality inlets, hooded and deep sump catch basins, sediment traps (forebays), and drainage channels

Source: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

Detention BasinsDetention Basins

TSS Removal Efficiency:– 60-80% average– 70% design

Key Features:– Large area– Peak flow control

Maintenance: low Cost: low to

moderate

Wet (Retention) PondsWet (Retention) Ponds

Removal Efficiency:– 60-80% average– 70% design

Key Features:– Large area– Peak flow control

Maintenance: low to moderate

Cost: low to high

Source: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

http://www.txnpsbook.org, 2002

Constructed WetlandsConstructed Wetlands

Removal Efficiency:– 65-80% average– 70% design

Key Features:– Large area– Peak flow control– Biological treatment

Maintenance: low to moderate Cost: marginally higher than wet ponds

Source: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

http://www.txnpsbook.org, 2002

Water Quality SwalesWater Quality Swales

Removal Efficiency:

–60-80% average–70% design

Key Features:

–Higher pollutant removal rates than drainage channels

–Transport peak runoff and provide some infiltration

Maintenance: low to moderate Cost: low to moderate

Source: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

http://www.txnpsbook.org, 2002

Infiltration Trenches/BasinsInfiltration Trenches/Basins Removal Efficiency:

–75-80% average–80% design

Features:

–Preserves natural water balance on site

–Susceptible to clogging

–Reduces downstream impacts

Maintenance: high Cost: moderate to high

Source: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

StormTech, subsidiary to Infiltrator Systems, Inc, 2002

Dry WellsDry Wells

Removal Efficiency:– 80% average– 80% design

On-site infiltration For untreated storm

water from roofs only (copper excluded)

Source: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

Sand and Organic FiltersSand and Organic Filters

Removal Efficiency:

–80% average–80% design

Design Features:

–Large area–Peak flow

control Maintenance: high Cost: high

Source: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

http://www.txnpsbook.org, 2002

Inlets and Catch BasinsInlets and Catch Basins

Removal Efficiency:

–15-35% average–25% design

Design Features:

–Debris removal–Pretreatment

Maintenance: moderate to high

Cost: low to highSource: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

Sediment Traps/ForebaysSediment Traps/Forebays

Removal Efficiency:

–25% average–25% design

Design Features:

–Pretreatment–Retrofit

expansion–Larger space

requirement than inlet.

Maintenance: moderate Cost: low to moderate

Source: MADEP/MACZM Massachusetts Stormwater Management, Volume 2: Stormwater Technical Handbook, March 1997

Innovative BMPs - Advanced SedimentationInnovative BMPs - Advanced Sedimentation

Removal Efficiency:– 50-80% average– 80% design

Design Features:– small area– Oil and Grease

control Maintenance: moderate Cost: moderate

Rinker Inc, 2002

Innovative BMPs - Sand FiltrationInnovative BMPs - Sand Filtration

Removal Efficiency:– 50-80% average– 80% design

Design Features:– small area– Nutrient and

pathogen (potential) Maintenance: moderate Cost: moderate Stormtreat Inc, 2002

Innovative BMPs - HydrodynamicInnovative BMPs - Hydrodynamic

Removal Efficiency:– 50-80% average– 80% design

Design Features:– small area– Oil and Grease

control Maintenance: moderate Cost: moderate

Vortechs Inc, 2002

Innovative BMPs – Media FiltrationInnovative BMPs – Media Filtration

Removal Efficiency:– 50-80% average– 80% design

Design Features:– small area– Oil and Grease

control Maintenance: moderate Cost: moderate

Stormwater Management Inc, 2002

Innovative BMPs – Inlet InsertsInnovative BMPs – Inlet Inserts

Removal Efficiency:– To be determined

Design Features:– Retrofit– Construction– Oil and Grease

control Maintenance: moderate Cost: moderate

http://www.stormdrainsfilters.com, 2002

Water Quality MonitoringWater Quality Monitoring

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

TARP- Technology Acceptance Reciprocity Program

CAILMAMDNJNYPAVATX

Performance Verification - TARPPerformance Verification - TARP

Storm Event Criteria to Sample2 More than 0.1 inch of total rainfall.2 A minimum inter-event period of 6 hours, where cessation of

flow from the system begins the inter-event period.2 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.

2 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 Set2 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.

Performance Verification - TARPPerformance 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.

Performance Verification - TARPPerformance Verification - TARP

Sample Data Quality Assurance and Control- Equipment decontamination,- Preservation,- Holding time,- Volume,- QC samples (spikes, blanks, splits,

and field and lab duplicates), - QA on sampling equipment- Packaging and shipping,- Identification and labeling, and- Chain-of-custody.

Performance Verification - TARPPerformance Verification - TARP

Calculating BMP Efficiencies (ASCE BMP Efficiencies Task 3.1)

Process efficiencies or removal rates should be determined from influent and effluent contaminant concentration and flow data.

– Efficiency Ratio, – Summation of Loads, – Regression of Loads, – Mean Concentration, and – Efficiency of Individual Storm Loads.Note: The Efficiency Ratio method is preferred.

ContactsContactsEric Winkler, Ph.D.

Director, Technical Services(413) 545-2853 (Voice)winkler@ceere.org

Susan Guswa, P.E.

Environmental Analyst(413) 545-2165 (Voice)guswa@ceere.org

Center for Energy Efficiency and Renewable Energy

Energy and Environmental Services160 Governors Drive

University of MassachusettsAmherst, MA 01003-9265

www.ceere.org/ees

Questions and AnswersQuestions and Answers