The Evolution of Stormwater and Rainwater Harvesting in Minnesota The Minnesota Stormwater Manual Updates and Examples Presented by: Dave Stark December 5 th 2016 ARCSA 2016 National Conference
Minnesota Stormwater Manual Minnesota Stormwater Manual Lead agency for manual Stormwater Go to source for stormwater information Contractors hired for technical work with oversight committees Minimal impact design standards (MIDS) Lead contractor for design standards and model Stormwater and rainwater harvesting wiki Lead contractor for manual updates
Rainfall Trends
2012 Duluth Flood
And the Weather
Water Use and Population Trends https://metrocouncil.org/wastewater-water/publications-and-resources/water-supply- PLANNING/MASTER-WATER-SUPPLY-PLAN-2015/Master-Water-Supply-Plan-Appendix-2.aspx
White Bear Lake A Wakeup Call on Water Supplies http://freshwater.org/wp-content/uploads/2016/04/groundwater-report-web_4-26-16.pdf
How is Stormwater Managed in Minnesota?
Minimal Impact Design Standards What is MIDS? Four basic components: 1. Stormwater volume performance goals 2. Calculator to standardize and quantify ( credit ) the benefits of LID BMPs 3. Design specifications for a variety of LID BMPs (continuing in Stormwater Manual update) 4. A model MIDS ordinance package https://stormwater.pca.state.mn.us/index.php/overview_of_minimal_impact_design_standards_(mids)
What are the Performance Goals? Most Sites Clay, Sites etc. Contaminated Off Site Retain on site 1.1 of runoff from new and/or fully reconstructed impervious surfaces Retain 0.55 of runoff from the new and/or fully reconstructed impervious surfaces AND Remove 75% of the annual TP load Achieve as much volume reduction as practicable AND Remove 60% of the annual TP load Off-site mitigation
MIDS Calculator and Practices Bioretention Permeable Pavement Swales Infiltration Basin Stormwater Disconnect, Iron Enhance Sand Filters etc. What is MIDS and how it is different WHAT S MISSING? RAINWATER AND STORMWATER CAPTURE AND ALL APPROVED USES Tree Trenches Green Roofs Sand Filter Stormwater Pond Wetlands
Minimal Impact Design Standards Ability To Link BMP s Rainwater Tank -> Infiltration Soil and Land Use -> Curve Numbers https://stormwater.pca.state.mn.us/index.php?title=mids_calculator
https://stormwater.pca.state.mn.us/index.php/stormwater_re-use_and_rainwater_harvesting Stormwater and Rainwater Harvesting -Wiki Contents Definitions Design Criteria Construction Specifications Operation and Maintenance Water Quality Considerations Cost benefit Considerations Case Studies Calculating Runoff Reduction Credits
Survey with Stormwater Wiki Update
Survey Summary Q-What is the source of the water you are using? Q-Why did you Implement the project? Q-What difficulties did you experience implementing the project?
Code Status Minnesota adopted the 2012 Universal Plumbing Code (UPC) with state amendments including Rainwater Harvesting on January 23, 2016. Stormwater or Graywater Re-Use Not Included Widespread use of stormwater and pond applications for outdoor irrigation. No current regulations on water quality.
Water Re-Use Interagency Effort Agencies Education and Research Funding http://www.health.state.mn.us/divs/eh/water/dwp_cwl/reuse/index.html
Clean Water Fund Water Reuse Project A comprehensive assessment of regulatory and nonregulatory approaches for ensuring safe and sustainable water reuse 1. Identify current support and barriers to water reuse 2. Develop recommendations for safe, sustainable water reuse practices and policies 3. Update plumbing codes and treatment standards to allow for safe and practical water reuse
What Water Sources Are Being Considered? Sources Stormwater Rainwater Wastewater Domestic Wastewater Graywater Industrial Process Water Subsurface water End uses Nonpotable water Flushing Irrigation Cooling Washing Industrial process Aquifer recharge Infiltration Direct injection Potable water
Support for Re-Use Mounting Public Health Collaborative
Innovative Funding Mechanisms Source: http://stpaul.maps.arcgis.com/apps/mapjournal/index.html?appid=0e9dab10476549548cfad673b915abfd
Upper Villa Park Stormwater Concrete Tank Overflow to Infiltration Chambers Harvesting Reuse http://www.srfconsulting.com/news/projects/upper-villa-park-stormwater-harvesting-reuse/
Oneka Ridge Golf Course Water Re-Use Irrigation Project 915 acre drainage area 75% Annual P Load Reduction 100 acre-feet in volume reduction 40-50% decrease in groundwater http://www.ricecreek.org/
http://mwmo.org/projects/st-anthony-stormwater-reuse-system/ St. Anthony Village Stormwater Reuse 15 acre capture 500,00 Gallons 20 acre irrigation 77.5% P Reduction
St. Louis County Motorpool Facility Outdoor irrigation and indoor vehicle washing Before After
St. Paul Saints Baseball Stadium Outdoor Irrigation and Toilet/Urinal Flushing
Hennepin Energy Recovery Center Capture water for reuse. Approximately 25 percent of the rain and snow falling on Target Field Station flows into two cisterns and is then reused in the Hennepin Energy Recovery Center (HERC). https://content.govdelivery.com/accounts/mnhenne/bulletins/baf8c4
Rainwater Harvesting Volume Reduction Treatment Train Conceptual Model Great Start to A Stormwater Treatment Train Volume Reduction through use Relies on Permeable Soils for Infiltration Does Not Address other Stormwater Figures by Foraste 2009
ARCSA Standard 78 Compliant Stormwater Pre-Treatment Trains
What is Your Design Objective? Various Stormwater Treatment Approaches What Does it Treat -Mainly TSS, floatable, hydrocarbons What doe it treat >80% TSS removal (d50 = 23µ) >75% Total Phosphorus reduction >50% Turbidity reduction
Modular Linked Systems For Rainwater and Stormwater Harvesting Stormwater Tank Ground Capture Sized Overflow From Tank 1 Plus Ground Area Various Treatment Methods -> TSS, P Reduction Pump and treat for outdoor use only (MN) Rain Tank Roof Top Capture Treat with 4 Step System to Maintain Quality Tank and Filter Overflow To Storm Trtmt. Pump and treat for outdoor or indoor uses
Rainwater and Stormwater Industry in MN Comprehensive harvest and re-use program that addresses a variety of source waters. San Francisco as a model. Residential and commercial included Plumbing codes updated to include Graywater Re-use Stormwater with proper treatment for interior use Increased coordination of education efforts. U of MN Stormwater/Septic Extension MN Irrigation Association MN Water Quality Association ARCSA/ASSE
Thank You Questions? I d like to thank and acknowledge the efforts of these colleagues who have lead these efforts and welcomed industry input. Anne Gelbman at MPCA for Information on MIDS Anita Anderson at MDH for Leading the Interagency Effort Kurt Leuthold at Barr Engineering On Modeling/Calculator Brett Emmons at Emmons and Oliver Resources Section Updates