Tracy - Urban Subwatershed Stormwater Retrofit Analysis
Upcoming SlideShare
Loading in...5
×
 

Tracy - Urban Subwatershed Stormwater Retrofit Analysis

on

  • 894 views

 

Statistics

Views

Total Views
894
Views on SlideShare
894
Embed Views
0

Actions

Likes
0
Downloads
4
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment
  • Describe the MCD partnership as a Joint Powers group serving 11 counties in the Metro area in 4 overall services
  • Our process uses on multi-agency partnerships
  • Our current focus is Urban subwatershed analysis with an agricultural component currently being developed
  • We apply analyses to three scales….1st decide which SW to work within (TMDL, Non-Degradation Plan, MS4 city requirements, existing WQ data, willing and able partner)2nd decide which catchments in the SW (described in following slides)3rd decide which sites within catchments (described…)After analysis completed, we can assist with selection of prime sites for optimized return on investment to assist in allocation cost share $Entire process ensures that the selection of individual BMP projects are in the optimal location, and have the optimal site-specific site design, to provide the best return on investment (best location, best project, best price)
  • There are 7 BMP locations we first screen each catchment for that are conducive to stormwater retrofits – each area has a set of specific bmps that are then considered
  • …these are the bmp families we considered
  • Map existing stormwater network and analyze performance – look for easy and inexpensive modifications to add or improve WQ treatment
  • Routing map
  • Screen each catchment for areas conducive to retrofits of various forms
  • Field reconnaissance investigation – considers site-specific limitations when selecting specific BMP’s
  • Identification of prime sites for bmp locations – provides a select list of addresses to visit when doing education and outreqach (canvasing for potential site installations) as opposed to random acts of conservation
  • Each prime catchment (those modeled for new treatment), is anlalyzed at three levels of treatment and reported on in a Catchmetnt Profile within the report
  • The top 10, or so, catchments, in terms of cost/benefit optimization, are presented in a summary table.

Tracy - Urban Subwatershed Stormwater Retrofit Analysis Tracy - Urban Subwatershed Stormwater Retrofit Analysis Presentation Transcript

  • Shawn TracyRestoration SpecialistMetro Conservation Districts (MCD)MCD SWCD’sAnoka – Carver – Chisago – Hennepin – Isanti – Ramsey –Scott – Sherburne – Washington - Wright
  • Anoka Ecological Wright Restoration Carver MCD Washington ChisagoSubwatershed Stormwater Assessment MCD Stormwater BMP Design Sherburne LRP Hennepin Scott Isanti Education Ramsey
  • Dan Anderson: http://www.flickr.com/photos/stonebridgedapper/ Urban Google Earth Sub-WS Restoration Rural/Ag
  • What it is It is not Urban stormwater retrofitting …a hydraulic or storm sewer Identification of the highest analysis/planning tool value stormwater BMP retrofit …primarily used for street- practices by location (e.g., $/LB- scaping or park development TP/YR) (secondary benefit) A Water Quality planning tool …an elaborate excuse just to get Supplement to existing analyses in more raingardens One (major) consideration in Capitol Improvement planning A Precise and relative model Labor investment and quantity/quality of geospatial and W.Q. data affects accuracy
  • Why an SRA? Massive effort needed to affect change in WQ Disproportionate (insufficient) funding resources Disproportionate (insufficient) labor resources TMDL implementation guidance Assurance of “bang-for-buck”Challenges Little-to-no outfall and source- area field data Limited time and budgets 25 SRA’s completed in 2.5 years by SWCD’s with at least 5 more currently being worked on
  • The Plus Side >30 years of pollutant accumulation, behavior and washoff data available >20 years of BMP performance data with more recent, state-of- science research (bench and field) Midwest city data (loading) Several water quality models based on this research If outfall data exists, can be calibrated to improve accuracy Can easily be modified (build- scenarios) Repeatable (precise) 25 SRA’s completed in 2.5 years by SWCD’s with at least 5 more currently being worked on Multiple-year to-do-list based on value (lbs/$/yr)
  • 1-Selection of Subwatershed2-Ananlysis of SW’s Catchments 3-Analysis of BMP’s by site
  • Scoping and Remote Data collectionDesktop AnalysisField ReconnaissanceTreatment modeling and cost analysisReport
  • Scoping Water body needs LGU needs Existing data review (quality and needs) Budgets and timeframes Stakeholder consensusDesktop AnalysisField ReconnaissanceTreatment modeling and cost analysisReport
  • Scoping and Remote Data collectionDesktop Analysis Catchment and/or pipeshed delineation Delineate and classify land uses Delineate and classify permeable surface soils Analyze existing WQ treatment / base load model First-tier elimination of catchments for retrofitting First-tier determination of WQ potential treatmentsField ReconnaissanceTreatment modeling and cost analysisReport
  • Scoping and Remote Data collectionDesktop AnalysisField Reconnaissance Visit existing BMPs Confirm/modify land-use and storm sewer data Confirm/modify initial BMP-family selection Selection of 1° and 2° BMP sites (parcels) Site-specific data collectionTreatment modeling and cost analysisReport
  • Scoping and Remote Data collectionDesktop AnalysisField ReconnaissanceTreatment modeling and cost analysis Development and optimization of BMP design Iterations of “train” and/or level of treatment by BMP quantity – load reduction estimates Estimates of installation and life-cycle costs Life-Cycle Cost analysisReport
  • Scoping and Remote Data collectionDesktop AnalysisField ReconnaissanceTreatment modeling and cost analysisReport Summary table – catchments ranked based on performance ($/lb/LCyr) Catchment profiles Analysis methods and data References
  • Subwatershed Catchment Site S1 C1 S2 SW #1 C2 S3 C3 S4 C… S5 S…
  • Existing Stormwater Ponds Storage Above Public Land Roadway Culverts STORMWATER BMP LOCATION Storage LargeParking Lots ANALYSIS Below Outfalls Within Storage in Conveyance ROW System
  • Extended Detention Existing Pond Wet Ponds ModificationOther Wetlands BMPS Swales Bioretention Infiltration Filtration
  • Pleasant Lake Stormwater Retrofit Assessment, 2011
  • Laek McKusick existing stormwater routing diagram, MSCWMO
  • Lily Lake Stormwater Retrofit Assessment, 2009, Middle St. Croix WMO
  • Pleasant Lake Stormwater Retrofit Assessment, 2011
  • Pleasant Lake Stormwater Retrofit Assessment, 2011
  • Pleasant Lake Stormwater Retrofit Assessment, 2011
  • Pleasant Lake Stormwater Retrofit Assessment, 2011
  • Howard Lake Stormwater Retrofit Assessment
  • 34-Acre Medium Density Residential Area Pollutant Amt/yearWater Runoff 963,715 ft3 TSS 12,900 lbs TP 35 lbs TKN 128 lbs Copper 0.73 lbs Lead 1.34 lbs Zinc 5.80 lbs First Tier possible BMP locations Lindstrom Retrofit Assessment, 2009, Chisago SWCD
  • EXISTING CONDITIONS RETROFIT OPTIONS Catchment-based Base Marginal Network Treatment By BMPCost/Benefit Analysis Loading Treatment Level 1 Level 2 Level 3 Existing BMP performance (%TP) 54% New Net % New Net % New Net % TP (lb/yr) 25.2 13.7 1.0 58% 1.9 62%Treatment TSS (lb/yr) 7887 6698 261 88% 357 89% Volume (acre-feet/yr) 21.90 0.00 0.00 0% 2.40 11% Square feet of practice (or, CU FT of Exc. 3 ft below 1500 storage for WP, ED, SW) outlet Moderately Extended Not yet BMP Type Wet Pond Complex Detention advisedMarginal Costs Bioretention Materials/Labor/Design $30,000 $51,000 Unit Promotion & Admin Costs* $250 $254 Total Project Cost** $30,250 $54,803 Annual O&M $0 $1,125 Term Cost/lb/yr (30 yr) $1,008 $1,554 add 6 RG in Retrofit Scenario: exc 3 ft on P27 19
  • Catchment or Retro Type Qty of TP TP Volume Overall Est. O&M Total Est. 3 1 Pond ID 100 ft Reduction Reduction Reduction Cost Term Term BMPs (%) (lb/yr) (ac-ft/yr) (years) Cost/lb- TP/yr LILY-03 B 12 10 5 4 $19,900 30 $313 LILY-04 B, PS, VS 8 10 3.3 2.9 $14,150 30 $313 LILY-01 B 11 10 4.4 3.6 $17,650 30 $315 LILY-02 B 11 10 4.5 3.7 $18,000 30 $315 LILY-12 B 18 10 3.2 2.5 $12,000 30 $316 LILY-07 B, VS 20 20 7 5.8 $24,000 30 $318 LILY-09 B 11 20 4.3 3.6 $18,450 30 $337 LILY-22 B 14 20 2.5 4.2 $22,320 30 $352 LILY-10 B, PS, F 7 10 2.9 2.4 $15,225 30 $353 LILY-21 B 12 20 2.2 3.6 $19,325 30 $353 2 P13-W PM n/a 50 20 0 $130,000 15 $433 2 P18-W PM n/a 50 30 0 $265,000 15 $589 Lily Lake Stormwater Retrofit Assessment, 2009, Middle St. Croix WMO
  • http://www.metrocd.org/