Cost analysis resources

From LID SWM Planning and Design Guide
Jump to navigation Jump to search

Misunderstandings about how operation and maintenance costs for LID practices compare to those of conventional stormwater facilities like detention ponds, oil and grit separators and swales has been one of the significant barriers to their acceptance in the United States and arguably worldwide. In comparison to conventional stormwater facilities, LID practices have lower life cycle costs, perform better and provide additional benefits, such as improved aesthetics, urban heat island mitigation, and air quality improvement (US EPA, 2013).[1] For example, in a controlled field study at the University of New Hampshire Stormwater Center (Houle et al., 2013), maintenance demands and costs were compared over the first 4 years of operation for seven different types of stormwater control measures (SCM), including conventional practices (vegetated swale, wet and dry ponds) and LID practices (gravel wetland, bioretention, porous asphalt, sand filter). Through estimates of annualized maintenance costs per unit drainage area treated and per unit mass of pollutant removed, they found that LID systems have lower marginal maintenance burdens and higher water quality treatment capabilities than conventional practices like detention ponds and swales. Activities associated with maintaining LID practices were found to be less expensive and more predictable than those for conventional systems.[2] For a recent review of international research on life cycle cost and benefit analyses of LID stormwater practices see Xu et al. (2019) [3]

The following collection of tools includes our own and external resources.

STEP LID Life Cycle Costing Tool (Ontario)[edit]

The Sustainable Technologies Evaluation Program has produced a life cycle costing tool specific to Ontario. STEP built the tool after evaluating LID practices and design scenarios for input costs, maintenance requirements, rehabilitation costs and practice designs relevant to Canadian climates. The tool is in a simple to use Excel format and is free to download. STEP LID Life Cycle Costing Tool

See the LID Life Cycle Costing Tool page for more about the tool along with cost estimates for common design scenarios, and cost comparisons by LID practice type and design configuration.

Green Infrastructure Optimization Tool (Great Lakes)[edit]

The Greater Lakes Green Infrastructure Optimization Tool gives a preliminary assessment of green infrastructure options. Land-cover types (and technologies) include: Existing and proposed buildings, existing and proposed paved parking areas, walkways and roadways, open space, pasture, meadow, brush, woodland/grassland, woods and bare soil.

GI tool from the Great Lakes Commission

Green Values Stormwater Toolbox (Great lakes, USA)[edit]

A free tool for evaluating the costs and benefits of green infrastructure. It is based on the hydrology of the Great Lakes region, and produced by the Center for Neighborhood Technologies, a non-profit organisation in the USA.

CNT's Toolbox webpage

CNT's Green Values calculator tool

United States Environmental Protection Agency (US EPA)[edit]

The US EPA's National Stormwater Calculator provides a regionalized, planning-level cost estimation tool for LID stormwater practices in the United States that has been recently updated. For an article describing the updated tool see Bernagros et al. (2021) [4].

US EPA National Stormwater Calculator tool

A collection of other cost-benefit analysis resources from the Green Infrastructure team at the US EPA can be found at the following link.

Cost benefit resources from US EPA

CIRIA's BeST tool (UK)[edit]

A tool which monetizes Ecosystem Services (ESS) and Triple Bottom Line (TBL) criteria to assess LID options (described as Sustainable Drainage Systems, SuDS). The tool guides the user to consider some or all of the co-benefits listed below . Whilst the relative values may be useful for assessing options, the currency of this model is in GBP (£).


  • Air Quality
  • Amenity
  • Biodiversity and Ecology
  • Building temperature
  • Carbon sequestration
  • Crime
  • Economic growth
  • Education
  • Enabling development
  • Flexible infrastructure
  • Flood risk
  • Groundwater recharge
  • Human health
  • Pumping wastewater
  • Rainwater harvesting
  • Recreation
  • Treating wastewater
  • Tourism
  • Traffic calming
  • Water quality of receiving water


See also[edit]


  1. United States Environmental Protection Agency (US EPA). 2013a. Maintenance of Low Impact Development: Communities are Easily Managing LID Practices. LID Barrier Busters Fact Sheet Series.
  2. Houle, J.J., Roseen, R.M., Ballestero, T.P., Puls, T.A., Sherrard, J. 2013. Comparison of Maintenance Cost, Labor Demands and System Performance for LID and Conventional Stormwater Management. Journal of Environmental Engineering. 139(7):932-938.
  3. Xu, C., Jia, M, Xu, M., Long, Y., Jia, H. 2019. Progress on environmental and economic evaluation of low impact development type of best management practices through a life cycle perspective. Journal of Cleaner Production. 213. pp. 1103-1114.
  4. Bernagros, J.T., Pankani, D., Struck, S.D., Deerhake, M.E. 2021. Estimating Regionalized Planning Costs of Green Infrastructure and Low-Impact Development Stormwater Management Practices: Updates to the US Environmental Protection Agency's National Stormwater Calculator. Journal for Sustainable Water in the Built Environment.7 (2): 04020021.