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New Stormwater Quality Requirements Building Industry Association February 14, 2007. Topics We’ll Cover Today. Background and need for requirements Overview of stormwater quality control measures included in the Design Manual Stakeholder outreach Schedule
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New Stormwater Quality Requirements Building Industry AssociationFebruary 14, 2007
Topics We’ll Cover Today • Background and need for requirements • Overview of stormwater quality control measures included in the Design Manual • Stakeholder outreach • Schedule • Review of development standard requirements: what’s new, what’s changing? • Challenges
Why Are We Doing This? • Required By Stateand Federal Regulations • Stormwater Permits issued to the local municipalities implement Clean Water Act and California Water Code • Permits require development standards to reduce pollutants in urban runoff to the “maximum extent practicable” • Protect Local Waterways and Associated Uses (e.g., fish, drinking water, recreation) • Development can negatively impact urban streams, due to increased imperviousness and pollutant loadings from automobile use and other activities
Negative Impacts of Development on Urban Streams • Reduced or no recharge for groundwater • Increased runoff volumes, peak flow rates and durations which can lead to downstream erosion • Increases in water temperature in creeks • Delivery of pollutants to creeks: • Sediment and construction-related pollutants • Pesticides and fertilizers (phosphorus) • heavy metals, oil & grease, and hydrocarbons • detergents and more
National studies have shown correlations between increased imperviousness in a watershed and stream/habitat degradation More pavement & roofs = impaired waterways
Background: Permit RequirementsSacramento Areawide Phase I NPDES Municipal Stormwater Permit • Current permit effective January 2003 – December 2007 • Sacramento Stormwater Quality Partnership includes 7 permittees: County of Sacramento and Cities of Sacramento, Citrus Heights, Elk Grove, Folsom, Galt and Rancho Cordova • Program began in 1990; requirements for development initiated in mid 1990’s • Permit required a Development Standards Plan (Dec 2003) to propose amendments to the local programs • Permittees required to amend standards by May 18, 2006
Background: Permit RequirementsCity of Roseville Phase II NPDES Municipal Stormwater General Permit • General permit issued to Roseville in 2003 • Development standard requirements are described in “Attachment 4” to the general permit • Roseville opted to proactively collaborate with Sacramento program to provide regional consistency for development community and share resources • Stormwater quality development standards will be new for Roseville
The Sacramento/Roseville Collaborative ProcessNew Stormwater Quality Design ManualControl measures included in the ManualStakeholder outreachSchedule
New Stormwater Quality Design Manual Project Goals • Create standardized, easy-to-use format to promote consistency and streamline the permitting process • Consolidate all stormwater quality design criteria in one manual • Tailor information to Sacramento Region • Integrate “low impact development” (LID; also known as runoff reduction) measures
New Stormwater Quality Design Manual • Primary audience: engineers, planners, architects, landscape architects, environmental consultants, public agency plan reviewers • Additional audience: developers, property owners, elected and appointed government officials, regulators, interested general public • Goal is to get people to use the manual at the earliest possible stage in site layout and planning – this requires early involvement of engineers and collaboration between planners, architects and engineers
Post-Construction Stormwater Quality Control Measures • Control measures installed during construction to reduce pollution in runoff from completed (post-construction) projects, for the life of the project • Three types addressed in new design manual: • Source control – prevent pollutants from contacting site runoff at the source • Runoff reduction – reduce volume of runoff discharged from the site (also known as “LID”) • Treatment control – remove or reduce pollutants that have been entrained in runoff
Examples of Control Measures Featured in Design Manual • Source Control: • “No Dumping” stamps on new storm drain inlets • Design details for waste management, loading and other areas that can generate pollution • Runoff Reduction: • Pervious pavement • Disconnected pavement and roof drains • Treatment Control: • Vegetated swales and filter strips • Detention basins/ponds
Runoff Reduction ControlsDisconnect Impervious Surfaces Divided Sidewalks Alternative Driveways
Runoff Reduction ControlsDisconnected Roof Drains Commercial Residential
Treatment Controls Bioretention: Stormwater Planters Portland State University City of Portland
Treatment ControlsVegetated Swales Old Way New Way
Treatment ControlsVegetated Swales Gateway Oaks Sacramento Expo Parkway Sacramento
Treatment ControlsSand Filters City of Sacramento Dept. of Utilities Parking Lot
Treatment ControlsWater Quality Detention Basins North Natomas
What Do Local Agencies Allow?Sacramento Stormwater Quality Partnership Two types currently acceptable*: StormVault® and StormFilter® (7.5 gpm ZPG media) by CONTECH *For current approved list, see www.sacramentostormwater.org
What Do Local Agencies Allow?City of Roseville • The City of Roseville is currently reviewing performance information on many of the stormwater treatment devices that are available on the market today • Prior to adoption of the new Stormwater Quality Design Manual, the City will post on their website a new list of approved proprietary stormwater treatment devices
Water Quality Treatment Controlswe can learn from others’ successes… Dublin Ranch water quality swales and detention basin
Runoff Reduction Measureswe can learn from others’ successes… Pervious pavement, Emeryville
Combination Approacheswe can learn from others’ successes… Divided sidewalks and vegetated swales Greenbriar Development, Livermore
How Are Redevelopment Projects Addressed? • Significant Redevelopment includes, but is not limited to: • Expansion of a building footprint; • Replacement of a structure; • Replacement of impervious surface that is not part of routine maintenance activity; and • Land-disturbing activities related to structural or impervious surfaces.
Significant Redevelopment (cont’d) • The standards described in the Design Manual shall apply only to the redeveloped area. • Exception: In cases where all drainage from the existing developed portion flows through the redeveloped portion, the treatment control measure must be designed for the entire contributing shed. • Check with local permitting agency for details.
What Is the Incentive for Using Runoff Reduction (Low Impact Development) Features? • Reduced volume of runoff • Less water to treat in stormwater quality treatment facilities • Possibly less land required for certain types of facilities (e.g., detention basins) • Possibly decreased size for other types of devices (e.g., underground vault) • Possible cost savings to developer
Stakeholder Outreach for the Design Manual • Stakeholder mailing list • Notifications when public draft is available • Web site: Background information, access to documents, project update fact sheets • Outreach to professional associations • Development focus group – meetings and early review opportunity • Public review draft available for 6 weeks
Design Manual Schedule • Agency review draft: July 2006 • Development focus group draft: December 2006 • Public review draft: February 16, 2007 • Available at web site • Written comments due: March 30, 2007 • Final manual: May 18, 2007 (regulatory deadline)
Design Manual Workshops • March 8, 2007 • 9:00 am to 12:00 pm • Woodcreek Oaks Golf Club • March 20, 2007 • 1:30 pm to 4:30 pm • City of Elk Grove Council Chambers
Development Standard RequirementsforSacramento County agenciesCity of RosevilleHow have or will standards change?What projects are affected?
Summary of Changes Being Madeby Local Agencies • Adoption of new/revised planning policies to better address water quality impacts of urban development • Implementation of new standards, effective: • May 18, 2006 (Sacramento County/cities) • Summer 2007 (City of Roseville)-see next slide • Publication of new Stormwater Quality Design Manual by May 18, 2007 • Standards address post-construction stormwater quality control measures.Construction-phase requirements are not changing at this time.
Effective Date for New Standardsin City of Roseville • After City adopts Design Manual (anticipated Summer 2007), all projects without an entitlement will be required to adhere to new development standards • Projects that received entitlement prior to Manual adoption will be encouraged to incorporate stormwater quality control measures as much as feasible
Examples of Policies Being Added to General Plans/Other Documents • Preserve, create or restore riparian corridors, buffers and wetlands • Limit disturbance of natural water bodies • Minimize impervious and directly-connected impervious areas (use infiltration where feasible) • Implement source and/or treatment controls to protect downstream water quality • Reduce downstream erosion
Projects Affected by Development StandardsResidential (Sacramento) • Old Standard • SFR< 100 acres (25 acres for Sac City); source control only • SFR≥ 100 acres (25 acres for Sac City); treatment control also req’d • MFR < 1 acre; source control only • MFR≥ 1 acre; treatment control also req’d • New Standard • SFR < 20 acres; source control, runoff reduction encouraged • SFR≥ 20 acres; treatment control also req’d • MFR: No Change
Projects Affected by Development StandardsResidential (Roseville) • Old Standard • None • New Standard • SFR < 10 lots; source control req’d, • SFR≥ 10 lots; runoff reduction and/or treatment also req’d • MFR < 1 acre; source control only • MFR ≥ 1 acre; treatment control also req’d
Projects Affected by New StandardsCommercial-Industrial (Sacramento) • Old Standard • < 1 acre impervious area; source control only • ≥ 1 ac impervious area; treatment control also req’d • New Standard • Old thresholds remain, and runoff reduction also encouraged now • Road projects < 5 acres impervious; source control only • Road projects adding ≥ 5 acres impervious; treatment control also req’d
Projects Affected by New StandardsCommercial-Industrial (Roseville) • Old Standard • None • New Standard • ≥ 100,000 sf; source control only • ≥ 1 acre impervious area; treatment control also req’d
Projects Affected by New StandardsAdditional Notes Re:Commercial-Industrial • Category includes public facilities, parks, schools and churches • Rooftop area included in impervious area calculation • Sites discharging to an existing regional treatment facility (e.g., detention basin) may not have to do additional on-site treatment
Challenges • General challenges • Applying standards to “Smart Growth” projects • Requirements for mixed use projects • Treatment strategies for roadway projects • Use of proprietary treatment devices
General Challenges • EARLY collaboration by the ENTIRE design team (e.g., planners, architects, engineers) is not taking place for the most part • Some of the features in the Manual may create conflicts with some existing agency codes and policies • There is resistance by engineers to some of the practices (e.g., pervious pavement)
General Challenges • Infiltration techniques will be difficult on many sites due to C and D clay soils • Some of the features may invite vector/mosquito problems if not properly designed, constructed and maintained
Implementation Challenges some features will not be plan or field checked by agency drainage engineers (e.g., disconnected roof drains) building department staff need to be brought on board
Challenges • Conflict between achieving “Smart Growth” objectives, and allowing space on these dense project sites for utilities, runoff reduction (LID) measures, stormwater quality treatment features and open space • However, the stormwater permits mandate that post-construction runoff is treated • Currently, there is no exemption or waiver option; such a program will take time to develop
WaiversWhat do the stormwater permits require? • “Permittees may propose a waiver program that would require any developers receiving waivers to transfer the savings in cost, to a stormwater mitigation fund” • “Funds may be used for projects … within the watershed of the waived project” • Waivers may be granted “when all appropriate treatment measures have been considered and rejected as infeasible” • The regulators must approve the waiver program prior to implementation