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Containment and Reduction of Stormwater-Derived Suspended Solids, Bacteria and Nutrients Using Aquatic Filter Barriers. Results From Drinking Water Reservoirs, a Flow-Restricted River and a Lake. Presented at the North American Lake Management Association Annual Conference Hartford, Connecticut
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Containment and Reduction of Stormwater-Derived Suspended Solids, Bacteria and Nutrients Using Aquatic Filter Barriers Results From Drinking Water Reservoirs, a Flow-Restricted River and a Lake Presented at the North American Lake Management Association Annual Conference Hartford, Connecticut October 2009
Containment and Reduction of Stormwater-Derived Suspended Solids, Bacteria and Nutrients Using Aquatic Filter Barriers NALMS 2009
Aquatic Filter Barrier Technology Aquatic Filter Barrier (AFB) Technologies primarily are alternative applications of an in-water filter fabric barrier to prevent migration of particulates in a water body or into a water intake NALMS 2009
Targeted Control Purposes Containment or Exclusion Suspended solids Turbidity Chemical contaminants Bacteria Plants or Animals (including planktonic eggs and larvae) Aquatic Filter Barrier Technology Water and Debris from Construction Site Downstream, Filtered Water NALMS 2009
Filtering Particulates Sub 100-micron range Suspended sediments 0.5 – 3.0 mm and larger Organisms Debris Planktonic or neustonic organisms Aquatic Filter Barrier Technology NALMS 2009
The Aquatic Filter Barrier NALMS 2009
The Aquatic Filter Barrier The AFB’s filter material is suspended by flotation billets and is sealed to the bottom by impermeable materials. The seal is optimized by engineering design. Mooring system hardware mounted on the structural skeleton of the AFB provides durable attachment points for the anchor lines, secured to the customized anchors. NALMS 2009
Filter Material Durability, Strength, and Permittivity One- or Two- Layer Concepts Custom Laser-Perforated for Targeted Protection and Exclusion Woven – “G-Weave” Aquatic Filter Barrier Components NALMS 2009
Strengthening Elements (system “skeleton”) Nylon Strapping Structural Netting UV Resistant, Strong Threads Built-in Sectioning Chain, Bottom and/or Collar Aquatic Filter Barrier Components NALMS 2009
Flotation Protection at the Surface Supports the AFB UV Resistant Materials Aquatic Filter Barrier Components NALMS 2009
Mooring System Sturdy Attachment Points on System Skeleton Custom-Fabricated Lines Adjustment Chain Anchors Designed According to Substrate Aquatic Filter Barrier Components NALMS 2009
Purpose: EPA Demonstration Project Control of stormwater-derived contaminants, bacteria, TSS, turbidity Field Study Full Scale AFB Laboratory Studies Fabric Blinding ProjectsWachusett Reservoir, MA NALMS 2009
Application Specifics Brook flow max ~11 cfs 350 ft AFB Curtain Deepest ~12 ft Manual compressed air cleaning option In place since 1998 ProjectsWachusett Reservoir, MA
Results Laboratory Varied: TSS up to 41.7%, Fecal to 41% 1 gpm/sf = max flow w/o blinding Full-scale Varied; TSS negative - 54% Turbidity (1.6 – 21 NTU) reduced to 1.3 – 2.5 NTU ProjectsWachusett Reservoir, MA NALMS 2009
Purpose Bring water withdrawal into compliance with Interim Surface Water Treatment Rule for Coliforms <= 100 mpn Out of compliance >6 months/yr based on 6-month running average ProjectsRye Lake/Kensico Reservoir, NY NALMS 2009
Application Specifics High runoff (two, 60-in culverts) AFB 650-feet long Max depth 25-feet Single layer, 8-oz non-woven, geotextile filter medium Deadman anchors at ends bear load; Concrete anchors for configuration 15-in dia polystyrene billets Demonstration Test System 1998 Permanent system since 2002 Limited maintenance ProjectsRye Lake, NY NALMS 2009
Results 3 sample events inside and outside, at ¼, ½, ¾ along AFB 5-day/wk sampling of intake InsideOutside Turbidity: 20 NTUs 1 NTU Coliforms: > 2400 MPN 22 MPN TSS: 9.9 mg/l 0.7 mg/l Brought and retained water intake in compliance ProjectsRye Lake, NY NALMS 2009
Purpose Years with high precipitation experienced frequent algal blooms, detrimental to the lake ecology and a nuisance to homeowners ProjectsLake Attitash, Northeast MA • One measure to reduce nutrient loading and limit algal blooms NALMS 2009
Application Specifics 140 feet long filter curtain averages 6 feet deep positioned well up in the Back River and full across the river Ends secured on the shore and mushroom anchors deployed upstream and downstream 10-foot section specially for passage of kayaks, canoes or small watercraft allow river flow over the top of the flotation during high flow events Projects Lake Attitash, Northeast MA NALMS 2009
Results Data collected by volunteers, not analyzed to date Initial observations were of reduced phosphates below AFB Primary observation: Reduced occurrences of bloom during wet weather (since 2003) Lake Association had repairs made during 2009 Projects Lake Attitash, Northeast MA NALMS 2009
Purpose EPA-funded short-term study Determine ability of the technology to achieve MA swimming standards – for bacteria and water clarity ProjectsCharles River, Boston, MA NALMS 2009
Application Specifics – Two Systems AFB 150 feet long Deepest is 6 feet Ends secured on the shore, Danforth anchors secure outside, sand bags on impermeable seal Floating Filter Pool 12 ft X 12 ft x up to 6 ft deep PVC framework Anchored with Danforth anchors ProjectsCharles River, Boston, MA NALMS 2009
Results Data collected by volunteers, not analyzed to date Initial observations were of reduced phosphates below AFB Primary observation – reduced occurrences of bloom during wet weather since 2003 Lake Association had repairs made during 2009 Projects Lake Attitash, Northeast MA NALMS 2009
Scoharie Reservoir Purpose Aquatic Filter Barrier Projects
Aquatic Filter Barrier Projects Scoharie Reservoir Application Specifics
Aquatic Filter Barrier Projects Schoharie Reservoir Results
Attitash Lake Purpose Aquatic Filter Barrier Projects
Attitash Lake Application Specifics Aquatic Filter Barrier Projects
Attitash Lake Results Aquatic Filter Barrier Projects
Gunderboom Projects – Ongoing New York City Waterfalls, Public Art Fund July-October 2008 Intake Filter Pools
Purpose EPA-funded short-term study Determine ability of the technology to achieve MA swimming standards for bacteria and water clarity ProjectsCharles River, Boston, MA NALMS 2009
Application Specifics – Two Systems AFB 150 feet long Deepest is 6 feet Ends secured on the shore, Danforth anchors secure outside, sand bags on impermeable seal Floating Filter Pool 12 ft X 12 ft x up to 6 ft deep PVC framework Anchored with Danforth anchors ProjectsCharles River, Boston, MA NALMS 2009
Results* . Projects Charles River, Boston, MA *Table 4: Maximum percentage improvements for multiple parameters on 7/17/02 NALMS 2009
Purpose Create a safe, pleasant atmosphere for beach-goers and swimmers with reduced bacteria levels ProjectsMamaroneck Village Beach, NY NALMS 2009
Application Specifics Tidal beach, 10-ft semi-diurnal Winter ice 800-feet long, deepest is ~30 feet Ends secured via concrete Deadman anchors, mushroom anchors secure against incoming tides Beach closed between oil spill and 2002 BPS install 1990’s system oil spill, 2002 system to 2009, new system this year ProjectsMamaroneck Village Beach, NY NALMS 2009
Results Reduced bacteria Reduced closures Increased clarity Increased beach and park use . Projects Mamaroneck Village Beach, NY NALMS 2009
Gunderboom Projects Ongoing New York City Waterfalls, Public Art Fund July-October 2008 Intake Filter Pools
Application of Aquatic Filter Barrier Technologies Requirements • Is adequate space available for fabric area required to meet flow through? • What particulate sizes are to be controlled – (the smaller the particles, the finer the filter AOS, lower filter medium permittivity and larger fabric area required)? • What is to be controlled associated with particulates (e.g., chemicals,bacteria)? • What is composition, concentration and size range of TSS that could cause clogging or blinding? • Is there a natural water movement to help clean the fabric or will some cleaning mechanism be required (e.g., air, periodic pressure wash or manual cleaning)? • If a containment system, will a pumping system be required to create flow through the fabric to achieve particulate reduction?
For Aquatic Filter Barrier Questions or More information on the Applications: Contact: Andy McCusker amccusker@gunderboom.com 207 653-6777 or Matt Brunner mbrunner@gunderboom.com 207 883-1777 NALMS 2009