Stormwater Manuals - The Good, the Bad and the Ugly. David J. Hirschman Center for Watershed Protection Getting in Step with Phase II Charleston, WV

Transcription

1 Stormwater Manuals - The Good, the Bad and the Ugly David J. Hirschman Center for Watershed Protection Getting in Step with Phase II Charleston, WV

2 Manual Overview Overview Review of State & Local Manuals What Constitutes a Good Manual? How Existing Manuals Measure Up You Get What You Ask For Notable Manual Components Creating Better Manuals CWP Stormwater Update

3 Manual Overview Manuals are the heart of stormwater management programs Technical information within manuals: Serves as a valuable reference for designers and plan reviewers Helps stormwater programs run more efficiently Helps ensure stormwater regulations are effectively implemented during design* * Isn t this the key to an effective stormwater management program?

4 Manual Overview The most effective manuals have two parts: Design Manual Detailed guidance for selecting, designing, reviewing and approving stormwater BMPs at development sites Used by design professionals and plan reviewers Can be an existing state or regional manual Policy and Procedures Manual Policies and procedures to support the local plan review process Used by plan reviewers, design professionals and administrative staff Should be prepared at the local level

5 Review of Existing Stormwater Manuals 43 Stormwater Manuals Reviewed 25 State, Provincial and Territorial Manuals* 18 Local Manuals Results Used to Develop a Manual Building Tool Provides links to the top 3 or 4 manuals for 50 different stormwater management topics, organized by category Design & Policy and Procedures * Full disclosure: CWP had a direct or indirect hand in more than 25% of them

6 Summary of Results Percent of US States that: Have a manual: 73%* Have a modern manual: 22% * Using a liberal definition of design manual

7 What Constitutes a Good Manual? A modern design manual should include: Unified Stormwater Sizing Criteria Special Criteria for Sensitive Receiving Waters* Special Criteria for Stormwater Hotspots Treatment Train Approach List of Acceptable Stormwater BMPs Detailed Stormwater BMP Design Guidance Stormwater Credits or LID Incentives* * Today s focus

8 How Existing Manuals Measure Up Percent of State Manuals With: Unified Stormwater Sizing Criteria: 25% Water Quality Criteria: 25% Recharge Criteria: 10% Channel Protection Criteria: 18% Flood Control Criteria: 25% Special Criteria for Sensitive Receiving Waters: 10% Special Criteria for Stormwater Hotspots: 12%

9 How Existing Manuals Measure Up Percent of State Manuals With: Treatment Train Approach: 27% List of Acceptable Stormwater BMPs: 16% Detailed Stormwater BMP Design Guidance: 29% Stormwater Credits: 14% More than 1 inch of Stackage : 100%

10 Manual Stackage A true test of how manuals really measure up...

11 One or More Center BMP Cartoons*: 100% * Or Center publication citations

12 You Get What You Ask For All joking aside Local stormwater managers, design professionals, and plan reviewers need good guidance for use at the site level Without modern guidance, we ll continue to get what we ask for, often with disappointing results

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14 Notable Manual Components Notable components of a modern stormwater manual include: Special Criteria for Sensitive Receiving Waters Stormwater Credits or LID Incentives These are relatively new stormwater management strategies that help link site design with watershed planning

15 Special Criteria to Protect Sensitive Receiving Waters Protect Coastal Resources Conserve Wetlands Protect Wetlands Protect Lake Water Quality Maintain Stream Quality

16 Special Criteria to Protect Sensitive Receiving Waters Protect Fisheries Protect Drinking Water Quality Protect Groundwater Quality Protect Forests and Farms

17 Most Manuals Don t Address Sensitive Receiving Waters

18 For example, the Minnesota Stormwater Manual includes special criteria for: Lakes Trout Streams Some Manuals Do Drinking Water Supplies Wetlands Impaired Waters

19 Stormwater Credits Purpose of stormwater credits or incentives: Promote greater use of certain better site design/low impact development techniques Reduce the size and cost of stormwater BMPs needed at site Provide economic incentive to use better site design/low impact development Use a simple and verifiable computational approach

20 While many manuals talk about the benefits of BSD/LID; Few manuals provide real incentives to make it happen during design

21 Philadelphia, PA Kansas City, MO James City Co, VA Minnesota Ontario Some Manuals Do

22 Creating Better Manuals Include modern stormwater manual content Learn from previous manual writing efforts Steal intelligently Use Manual Builder tool Adapt existing content to local conditions Involve stakeholders Train users Design professionals Plan reviewers

23 CWP Stormwater Update Manuals Resources Ongoing Research Websites:

24 The Urban Subwatershed Restoration Manual (USRM) Series CWP Resources Available through our website:

25 Manuals Manual 2: Methods to Develop Restoration Plans for Small Urban Watersheds Step-by-step guidance to develop, adopt and implement restoration plans Features 32 different desktop analysis, field assessment, stakeholder involvement and restoration management methods Detailed info on plan scoping and budgeting

26 Manuals Manual 3: Stormwater Retrofit Practices Expected March 2007 Outlines an approach to systematically find, design, rank and deliver stormwater retrofits to meet local watershed restoration objectives Detailed info on BMPs in retrofit situations

27 Manuals Urban Watershed Forestry Manual Three-part manual series on using trees to protect and restore urban watersheds Available through our website (free download):

28 Resources Wetlands and Watersheds Website and Article Series Available through our website (free download):

29 Resources Smart Watershed Benchmarking Tool Developed to measure integration and activity of 14 municipal watershed restoration programs 56 individual benchmark questions, total 100 pts (plus extra credit) Benchmarks based on survey of 50 communities across country Tested in 4 communities in 2005

30 Ongoing Research Street Sweeping and Storm Drain Research

31 Ongoing Research Georgia Coastal Stormwater Supplement Research on factors affecting BMP design and performance in the coastal plain Results will be used to develop a coastal stormwater supplement to the Georgia Stormwater Management Manual Will guide stormwater design along the Georgia coast