Improved Stormwater Management

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Improved Stormwater Management Site Design
Water as an asset, rather than a liability.
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Improved Stormwater Management Site Design

• Alternative stormwater drainage and site design
  approaches can
• Reduce runoff volumes 20 to 70 percent
• Reduce pollutant loads 60 to 90 percent
• Reduce site development costs by 1000 to 4000
  per residential lot, and 4000 to 10,000 per
  commercial or industrial lot

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Improved Stormwater Management Site
DesignRecent Regional Flood Damages
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Improved Stormwater Management Site Design

• Recommended site design philosophy
• Reduce the amount of impervious surface area
• Use the landscape to naturally filter, absorb,
  and recharge stormwater runoff

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Improved Stormwater Management Site
DesignRecommended Approaches

• Naturalized detention basins
• Natural drainage and infiltration
• Reduced imperviousness (e.g., permeable paving
  and alternative development designs)
• Cluster development / planned unit developments

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Improved Stormwater Management Site Design
Recommended Approach Natural Stormwater
Detention Basins
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Improved Stormwater Management Site
DesignRecommended Approach Natural Stormwater
Detention Basins
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Improved Stormwater Management Site
DesignRecommended Approach Natural Stormwater
Detention Basins
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Improved Stormwater Management Costs of Natural
Stormwater Detention Basins

• Natural wet bottom basin saves approximately 275
  per household for a 40-acre residential
  development over conventional wet bottom basin
  (Price, 1994, 1995)
• Savings are realized in shoreline stabilization
  where riprap lining costs are roughly double the
  cost of wetland plantings

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Improved Stormwater Management Recommended
Approach Natural Drainage and Infiltration
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Improved Stormwater Management Recommended
Approach Natural Drainage and Infiltration
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Improved Stormwater Management Recommended
Approach Natural Drainage and Infiltration
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Improved Stormwater Management Recommended
Approach Natural Drainage and Infiltration
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Improved Stormwater Management Recommended
Approach Natural Drainage and Infiltration
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Improved Stormwater Management Costs of Natural
Drainage and Infiltration

• Curb/gutter/storm sewers 40 to 50 per linear
  foot, 2 to 3 times the cost of a vegetated swale
• Lake County example cost savings of 70,000 per
  mile of road for a typical ½-acre lot residential
  subdivision, or nearly 800 per residence

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Improved Stormwater Management Recommended
Approach Permeable Paving
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Improved Stormwater Management Site
DesignLocal Examples

• Lake County Watershed Development Ordinance
• Prairie Crossing Conservation Development
• Mill Creek Conservation Development

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Lake County Watershed Development Ordinance

• Recommends minimized impervious surface and soil
  compaction, and maximized infiltration of runoff
  at the development site
• Regulates floodplain development
• Protects water quality by requiring buffers for
  streams, wetlands, lakes, and ponds

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Prairie Crossing Conservation Development

• Roadside swales convey runoff to restored
  prairies
• Filtered runoff discharged into polishing
  wetlands
• Large detention basin doubles as a recreational
  lake

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Mill Creek Conservation Development

• Natural drainage
• Cluster development
• Open space
• Protected stream corridor and flood plain

Graphic courtesy of Kane County Development
Department.
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Related NIPC Publication