Playground Infiltration Basin
Playground Infiltration Basin
Playground Infiltration Basin
Where is this located? It is downhill of the picnic building near the play structure.
What’s special about this place? The park at Squalicum Creek is a highly contoured area taking advantage of terrain to define and direct the stormwater to flow certain directions. It mimics the work of nature. The playground has drains underneath it that collect all the runoff water which is then piped to these infiltration basins where the water seeps into the ground.
About Infiltration Basins
Infiltration basins are low areas in the ground that temporarily collect runoff where it has time to soak gradually into the ground. These basins are usually dry except after a heavy rainfall. They are useful in residential and other urban settings to hold extra runoff and reduce the flow of runoff into streams. They require the right kind of soils which allow water to soak in. Soil texture and plant roots create spaces in the soil for water to flow into. Different soils absorb runoff at different rates; it depends on how wet the soil already is, and the amount of rainfall at the time. Sandy soils have spaces between each grain which allow water to soak in more quickly. Once water soaks into the basin area, it stays there until it’s taken up by plant roots or filters down and recharges the groundwater. Some of the water evaporates during warm summer months.
Water Quality Benefit: They improve water quality by settling and filtering out pollutants which prevents pollutants from being carried into streams. They also recharge groundwater. However, fast flowing water may not be in contact with the soil long enough for any treatment. When trees are planted in or left around infiltration basins, they can shade buildings and parking lots or other paved areas which reduces runoff temperatures. Preventing warmer runoff from entering streams is good for the creatures that live there.
Water Quantity Benefit: Infiltration basins are commonly used when there is an opportunity to reduce surface runoff. They are designed to imitate the natural movement of water and evaporation. By infiltrating some of the runoff, this reduces flows downstream. Anything you can do to hold water upstream reduces the size of piping needed downhill. Infiltration is the quickest way to address stormwater flows.

Drains 2 acres.
Where does this stormwater runoff come from? Runoff comes from the picnic shelter, play area and the grassy areas on the hill adjacent to the basin.
Where does this stormwater runoff flow next? Most of the runoff soaks into the soil of the infiltration basin, eventually to recharge groundwater.
image gallery
select any photo to see a slideshow
Stormwater flows from the playground down to this infiltration basin with two inlets. Water that flows here is treated when it soaks into the ground. There is no drain.
This aerial photo shows how water flows across the terrain to the infiltration basin near the playground.
The playground has drains underneath it that collect the rainwater which is piped to nearby infiltration basins where it seeps into the ground.
See how this shallow trench is designed to temporarily store runoff. These depressions in the ground require the right kind of soils so that water can soak into the ground.