Economic Tidbits:

  • The individual benefits of specific tools (e.g., clustering, native landscaping, bio-swales, etc.) cannot be separated from the overall benefits of a complete site design by combining these techniques together. Ten case studies show an impressive 36% savings where holistic conservation design treatments were used over conventional practices.
  • Maintenance cost savings range between $3,950 and $4,583 per acre per year over ten years for native landscaping approaches over turf grass approaches.
  • At the site level, significant cost savings can be achieved from clustering, including costs for clearing and grading, stormwater and transportation infrastructure, and utilities.
  • Swale conveyance is cheaper than pipe systems, by some claims as much as 80%.

Conservation Development Savings (2005):

  • Natural landscaping $4,400-$8,850 cheaper per acre
  • Long-term maintenance cost savings over $4,000 per year
  • Pervious pavement can reduce total costs by up to 30%
  • Swale conveyance up to 80% less expansive than pipe/curb and gutter
  • Conservation streets $329 less per foot

Low Impact Design Savings from 17 Case Studies

  • Capital costs decreased in 16 out of the 17, from 15 to 80%
  • In all cases, LID provided other not-monetized benefits including:
    • improved aesthetics
    • expanded recreational opportunities
    • increased property values due to proximity to open space
    • increased total number of units developed
    • increased marketing potential, and faster sales
    • reduced runoff volumes and downstream pollutant loadings
    • reduced incidences of combined sewer overflows


  1. Changing Cost Perceptions: An Analysis of Conservation Development. 2005. Prepared for the Northeastern Illinois Planning Commission by the Conservation Research Institute.
  2. Reducing Stormwater Costs through Low Impact Development (LID) Strategies and Practices, EPA publication number 841-F-07-006, December 2007.
  3. Site Plan Review: Procedures for Environmental Analysis. Association of New Jersey Environmental Commissions. Mendham, NJ 07945.
    ( - 219 KB)
  4. EPA Watershed Academy. Growth and Water Resources. (

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