King CountyFor more information about this layer please see the GIS Data Catalog . Retention or detention pond is a Flow Control (FC) facility. It is an infiltration system specifically designed to capture, store and then slowly release stormwater runoff downstream or into the ground. A detention pond stores accumulated stormwater runoff and slowly releases it downstream. A flow control structure regulates the release rate of the stored water. Some detention ponds are combined with water quality treatment ponds (i.e., wetponds) which are intended to have some water in them on a permanent basis. A retention or infiltration pond collects stormwater and allows the water to soak into the soil. This infiltration process helps recharge groundwater.ArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/0d02b03d4eb14c2ca23ecb9464ae5919_0engKing County GIS Open DataPublicRD Facility maintained by King County Roads Division [Washington (State)--King County]Web servicesWashington (State)--King CountyWashington (State)Last Modified: 2025-08-04