iSWM Program Implementation
Lesley Brooks, P.E., CFM
Mike Wayts, P.E., CFM
Karen Walz, FAICP
Agenda
Overview of iSWM
Why Address iSWM Issues?
State and Federal Regulations Regarding Water Quality
Benefits of Adopting iSWM
How to Adopt iSWM
Cities That Have Adopted iSWM
Overview of iSWM
Where Does iSWM Come From?
People Behind the iSWM Program
iSWM Implementation Committee (IIC)
TEAM*
*Team included:• Andy Reese• Karen Walz• Katrina Martich• Jonathon Young• Dr. Caffey
Overview of iSWM Program
iSWM Criteria Manual
(For Adoption)
iSWM Technical Manual
(For Reference)
iSWM Tools
(For Reference)
iSWM Program Guidance
(For Reference)
iSWM Program
http://iswm.nctcog.org
Development Process:• Move the discussion of stormwater to the forefront of the process– Conceptual
– Preliminary
– Final
• Encourage innovative approaches
• Comprehensive program to address water quality, streambank protection, flood control, and construction impacts.
Overview of iSWM Program Page 8‐13 and 69‐79 of Criteria Manual
Overview of iSWM Program
Options:1. Use integrated Site Design Practices. Measured with a point system based on the percentage of natural features on a site and the percentage of practice utilized.
2. Treat the runoff resulting from rainfalls of up to 1.5 inches (85th percentile storm).
3. Assist in implementing off‐site community stormwater pollution prevention programs/activities.
Water Quality * Streambank Protection * Flood Control
Page 6 of Criteria Manual
Overview of iSWM Program
Options:1. Reinforce/stabilize downstream conditions.
2. Install stormwater controls to maintain or improve existing downstream conditions.
3. Provide on‐site controlled release of the 1‐year, 24‐hour storm event over a period of 24 hours.
Water Quality * Streambank Protection * Flood Control
Page 6 of Criteria Manual
Overview of iSWM Program
Options:1. Provide adequate downstream conveyance systems.
2. Install stormwater controls on‐site to maintain or improve existing downstream conditions.
3. Maintain existing on‐site runoff conditions in lieu of a downstream assessment.
Water Quality * Streambank Protection * Flood Control
Page 6 of Criteria Manual
Overview of iSWM Program
Downstream AssessmentsChanges in flow timing must be considered when installing detention controls. If placed on the downstream end of a watershed may be holding back flows till the upstream peak reaches it. Study may show that detention is not necessary.
Where to study to? • Zone of Influence (10% Rule) • Adequate Outfall
3 Storm events:Streambank Protection: 1‐yrConveyance Storm: 25‐yrFlood Mitigation Storm: 100‐yr
10 acres
40 acres80 acres
120 acres
190 acres
Site A
Site B
Page 5 and 26 of Criteria Manual
Overview of iSWM Program
Construction
Chapter 4 of Criteria Manual
Why Address iSWM Issues?
Public Safety
• Flooding is the most destructive natural disaster in terms of economic loss to Texas.
• Texas has the most flood related deaths in the nation in the past 36 years.
Presidential Disaster Declarations 1964‐2007
Erosion
Water Quality
• Texas has 651 impaired water bodies
• Each of the major rivers in North Texas has segments that don’t meet water quality standards
• Lower water quality in reservoirs means higher costs for water treatment
• Recreational opportunities and quality of life are reduced by lower water quality in streams, rivers and lakes
Water Quality
Sustainability
Better Design
• Uses site’s natural features
• Neighborhoods with character
• Higher property values
• Increased quality of life
To Meet Regulations
NPDES Permitting Program
MS4s(Post Construction
Controls)
Phase I
Phase II
Construction Industrial
State and Federal Regulations Regarding Water Quality
TCEQ Permitting Program
TPDES Permitting Program
MS4s(Post Construction
Controls)
Phase I
Phase II
Construction Industrial
Phase I MS4 Permit
• Phase I MS4 permits in process of renewal– New Garland permit referenced by TCEQ as example of future Phase I MS4 permit style
– Phase I permits will trend toward Phase II style– Eventually Phase Is will be covered under same permit as Phase IIs
• Phase I MS4 focus areas– Development/redevelopment– Storm mapping– Construction waste management– Public outreach
Phase II Permit
• Phase II Permit are in their final year.
• MS4’s required to fully implement Stormwater Master Plan by end of permit term.
Illicit Discharge Detection/Elimination
Public Education/ Outreach
Post‐Construction Management
Phase II MS4: Six Minimum Control Measures
Public Involvement
Construction Site Runoff Control
Good Housekeeping
Current Phase II MS4 Permit
• Must address runoff from new development and re‐development of 1 acre or more
• Must ensure controls are in place that would prevent or minimize water quality impacts. The permittee shall:– Develop and implement strategies which include a combination of structural and/or non‐structural BMPs appropriate for the community;
– Use an ordinance or other regulatory mechanism to address post‐construction runoff to the extent allowable by state and local law; and
– Ensure adequate long‐term operation and maintenance of BMPs.
Future Phase II MS4 Permit
• Phase II Permits– February 2012: Draft new permit to be issued
– August 2012: Initial permit expires and final new permit to be issued
– Key proposed changes• Dry weather field screening for larger cities
• Street sweeping for larger cities
• Industrial site oversight
• Additional development/redevelopment requirements
• Address roads
• Inspection of BMPs for larger cities
Future Phase II MS4 Permit
• Four tiers proposed– <10,000
– 10,000 – 40,000
– 40,000 – 100,000
– >100,000
• Smallest tier would be subject to similar requirements as 2007‐2012 permit
• Largest tiers would be subject to more extensive requirements
EPA Guidelines Report
• Current approaches do not work
• Focus on volume control, impervious area
• Full flow regime should be evaluated
• Emphasize LID
• Watershed boundaries, not political
• More industrial site tracking
• Integrate construction, industrial under MS4 authority
National Research Council (NRC) 2008 Report
EPA Actions: EISA Section 438
• Stormwater runoff requirements for federal development projects
– Federally‐funded facilities with a footprint that exceeds 5,000 square feet
• Two options:
– Maintain predevelopment hydrology (temperature, rate, volume duration) to 95th
percentile on‐site
– Employ systems to infiltrate, evapotranspirate, and/or reuse precipitation
EPA Actions: Stormwater Rulemaking
• Focus– Area of regulation (MS4 boundaries, roadways)
– Post‐construction control
– Retrofits to existing development
• Schedule
2009 2010 2011 2012 2013
Oct. 2009: Started updating rules
2010: Collected info. from the public
Nov. 2012: Final Rule
Sept. 2011: Draft rule
Benefits of Adopting iSWM
Benefits of Adopting iSWM
• The community benefits from iSWM because:– Retaining natural drainageways and open spaces creates better neighborhoods & communities
• Unique character• Access to nature• In some cases, offers trails for health & mobility
– Places with natural areas appeal to a growing segment of the market
– Working with nature means communities that remain desirable over the long term
– Less erosion means fewer concerns about property damage and loss
– Reduced flooding saves lives & property
Benefits of Adopting iSWM
• The municipality benefits from iSWM because:– Costs for major ‘grey infrastructure’ projects are reduced
– On‐going operation and maintenance costs mean lower budget impacts annually
– Reduced erosion means fewer safety & liability concerns
– Reduced flooding saves lives & property, and reduces demands on public safety personnel & budgets
– Consistent approaches within a watershed will be more effective
– A greener community is likely to be more sustainable –and more desirable – over time
Benefits of Adopting iSWM
• The review process benefits from iSWMbecause:– There’s no need to ‘reinvent the wheel’
– Time for permitting may be reduced
– Developers don’t need to know and follow unique procedures or requirements for individual communities
– Consistency supports other watershed‐level initiatives
Benefits of Adopting iSWM
• Meet State and Federal Regulations– NCTCOG has been in close contact with TCEQ regarding iSWM
• A Regional Program with Regional Recognition
Benefits of Adopting iSWM
• Ongoing Assistance From COG
– Training for Staff and Developers
– Support Data
Benefits of Adopting iSWM
• Customizable Thru Local Provisions– Also Chapter 5
Benefits of Adopting iSWM
• Cost savings in development of individual manuals
How To Adopt iSWM
Have you Paid Into the Development of iSWM?
• iSWM™ is trademarked/copyrighted
• Use requires a licensing agreement with NCTCOG
• Payment based on City population
• Must be a member of the Regional Public Works Program in year of adoption
• Cities are encouraged (but not required) to continue participation to support manual maintenance, updates, training, etc.
COG Policy on Implementation
iSWM Element Points for Element
City Points
3 – Step Review Process (Concept, Preliminary, Final) 15 Water Quality Option 1: integrated Site Design Practices 10 Water Quality Option 2: Treat the Water Quality Protection Volume 10 Water Quality Option 3: Off‐Site Pollution Programs/Controls 10 Downstream Assessment for 3‐Storm Events (Streambank Protection, Conveyance, Flood Mitigation) 15 Streambank Protection* (Require Options 1, 2 and/or 3) 15 Flood Mitigation** (Require Options 1, 2 and/or 3) 15 integrated Construction Criteria 10Points Available 100 100Minimum Points Required 70 70City Score
* Requires Downstream Assessment**Requires Downstream Assessment if using iSWM Criteria. As an alternative, Community qualifies for Flood Mitigation points if a community‐wide drainage study / master plan has been developed and no development is allowed in the fully developed 100‐year floodplain.
• Community must be a current participant of the Regional Public Works Program.
• Community must adopt the iSWM Criteria Manual for Site Development and Construction (Manual) with Local Provisions as desired – OR – the Community must incorporate or reference portions of the Manual into codes, ordinances, drainage manual, etc.
• Community’s adoption or incorporation of elements of the iSWM Criteria Manual for Site Development and Construction must meet a minimum of 70 points in accordance with the table.
• Note that no License Agreement is required for use of the iSWM Technical Manual.
COG Policy on Implementation
• Need 70 points, so 30 points to spare.
iSWM Element Points for Element
City Points
3 – Step Review Process(Concept, Preliminary, Final) 15Water Quality Option 1: integratedSite Design Practices 10Water Quality Option 2: Treat the Water Quality Protection Volume 10Water Quality Option 3: Off‐Site Pollution Programs/Controls 10Downstream Assessment for 3‐Storm Events (Streambank Protection, Conveyance, Flood Mitigation) 15Streambank Protection* (Require Options 1, 2 and/or 3) 15Flood Mitigation**(Require Options 1, 2 and/or 3) 15integrated Construction Criteria 10Points Available 100 100Minimum Points Required 70 70City Score
• Lots of possible combinations.
• Set up meetings with COG to discuss if unsure.
Adoption Method
• Adopting Criteria Manual or Creating Separate Ordinance?
• Adopting the Criteria Manual– Criteria Manual must be referenced in an ordinance
– Subdivision only for new development, not redevelopment
– Zoning covers new development and redevelopment
Criteria Manual
• What’s in the Criteria Manual?– 84 pages, as is
• Chp. 1: Overview of iSWM Criteria Manual
• Chp. 2: integratedDevelopment Process
• Chp. 3: integrated Design Criteria
• Chp. 4: integrated Construction Criteria
Adoption Method
• Adopting through Separate Ordinance– Will need to develop ordinance with requirements for water quality, streambank protection, and flood control.
– Is it referenced in Subdivision and Zoning?
– Is it referenced on development review checklists?
Where to Start
• Review Criteria Manual and your communities goals
• Create a committee of decision makers
Have to know where you are to know where you’re going.
• Items to review include:–Development Process– Existing Criteria– Existing Ordinances
Who will be Involved
Review Development Process
• iSWM has 3 development review stages:– Conceptual
– Preliminary
– Final
• What are your steps?
• What is the earliest stormwater is discussed?
• Could that discussion be moved earlier?
Establish Local Provisions
• Compare iSWM Criteria Manual to Existing Criteria Manual
• Decide if any changes are needed
• Makes those changes in the local provision box
• Large changes can be inserted into Chapter 5
• If adopting through separate ordinance, include iSWM criteria into ordinance
Review Ordinances
• When local provisions are drafted, review ordinances to determine if there are any conflicts.
• Make changes in the ordinances or local provisions to remove conflicts.
• Conflicts addressed by variance may inhibit some developers.
Other Considerations
• Affect on Development– Involving and educating the development community
• Maintenance Impacts– Private vs. public maintenance
• Increase in Review Process Time and Effort– Increased meetings mean increased staff responsibilities
• What happens when the manual is updated by COG?
Cities That Have Adopted iSWM
Cities That Have Adopted iSWM
Feedback from City Leaders
• Why did you decide to adopt iSWM?
• What difference has it made?
• What do you hope it will accomplish?
• Who was involved in the implementation?
• What was you path of implementation?
• What advice would you give other communities?
Feedback from City Leaders
• Why adopt iSWM? – We were referencing another City’s manual who adopted iSWM so followed suit. Made a few changes based on local needs.
– Trying to move towards more open space and more natural sites. More about aesthetics than water quality. iSWM gave us the opportunity to put “encouragements” into writing.
• What difference has it made? – One development has had significant drainage issues. Used iSWM to design a detention pond that will serve as sediment basin during construction and retention pond after construction.
Feedback from City Leaders
• What do you hope it will accomplish? – Hope it will set a standard that developers and designers can reference that will increase the quality of stormwater management in the region, as well as within the City limits.
– We would all benefit from cities having the same codes. We should all use iSWM as closely as possible to the way it is written for drainage design as well as water quality design. This will benefit the development and consulting industry in making for an easier transition to these requirements, and it will shorten the learning curve for all of us. We also reduce drainage related lawsuits if all cities have the same standards. Texas drainage law is vague, protection from liability depends on all engineering experts having agreement on acceptable industry practices.
Feedback from City Leaders
• Who was involved in implementation? – Environmental Services and Engineering Department. Future updates will involve the Planning Department and City Management.
• What was your path of implementation? – Based on another City’s adoption. Reviewed their local criteria and made changes where necessary.
• What advice do you have for other communities? – Seems overwhelming in the beginning. But, once you get into
the nuts and bolts and compare that to your current drainage requirements there are not that many differences. The water quality standards included in iSWM are new to most cities in our region, and while they are based on design standards used in other parts of the US, only time will tell how effective they are in our area. But no one should be afraid to try something new.
Lesley Brooks, PE, [email protected]‐217‐2248
Mike Wayts, PE, CFM [email protected]‐217‐2222
Karen Walz [email protected]‐320‐1154
QUESTIONS?Jeff [email protected]‐695‐9212
Jack [email protected]‐695‐9220
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