Volume of water generated from rain and snowmelt flowing over (that is, without soaking into the ground) land indirectly or directly controlled by the organization during the reporting period.
Volume of water generated from rain and snowmelt flowing over (that is, without soaking into the ground) land indirectly or directly controlled by the organization during the reporting period.
Organizations should footnote all assumptions used, including which tools or methodologies were used to measure stormwater runoff.
This metric is intended to capture the volume of water that runs off (flows over without being absorbed by) land indirectly or directly controlled by the organization during the reporting period.
Organizations may use modeling tools to calculate the volume of stormwater runoff. For small sites, the U.S. EPA's National Stormwater Calculator (https://www.epa.gov/water-research/national-stormwater-calculator) and the Green Values National Stormwater Management Calculator (https://greenvalues.cnt.org/national/calculator.php) may be useful. For larger sites, the U.S. EPA's Storm Water Management Model (SWMM; https://www.epa.gov/water-research/storm-water-management-model-swmm) or HydroCAD (https://www.hydrocad.net) may be useful.
June 2022 - IRIS v5.3 Released (current version)
Immaterial change. Minor revisions to definition and usage guidance for clarity.
January 2020 - IRIS v5.1 Released
New metric. Stormwater Runoff (OD6737) was developed via the IRIS+ Sustainable Water Management Expert Subgroup.