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

Sources:

  1. Changing Cost Perceptions: An Analysis of Conservation Development. 2005. Prepared for the Northeastern Illinois Planning Commission by the Conservation Research Institute.
    (http://www.nipc.org/environment/sustainable/conservationdesign/cost_analysis/)
  2. Reducing Stormwater Costs through Low Impact Development (LID) Strategies and Practices, EPA publication number 841-F-07-006, December 2007.
    (http://water.epa.gov/polwaste/green/costs07_index.cfm)
  3. Site Plan Review: Procedures for Environmental Analysis. Association of New Jersey Environmental Commissions. Mendham, NJ 07945.
    (http://www.anjec.org/pdfs/SitePlanReview.pdf - 219 KB)
  4. EPA Watershed Academy. Growth and Water Resources. (http://water.epa.gov/learn/training/wacademy/archives.cfm)

Other Useful Resources: