What is an Infiltration Basin?

An infiltration basin, also known as a recharge basin or a stormwater basin, is a type of stormwater management facility that is designed to capture and treat rainwater runoff. It is a shallow depression in the ground that collects stormwater and allows it to infiltrate into the soil, replenishing groundwater supplies and reducing the risk of flooding.

How does an Infiltration Basin work?

An infiltration basin works by capturing stormwater runoff from impervious surfaces such as roads, parking lots, and rooftops. The basin is designed to temporarily store the runoff and allow it to slowly infiltrate into the ground. This process helps to remove pollutants and sediments from the stormwater before it reaches nearby water bodies, such as rivers and lakes.

When stormwater enters the infiltration basin, it is directed into a series of sedimentation ponds or forebays. These ponds are designed to trap larger particles and sediments, preventing them from entering the infiltration area. The water then flows into the main basin, where it is spread out over a large surface area to maximize infiltration.

Benefits of Infiltration Basins

Infiltration basins offer several benefits for stormwater management and the environment. Firstly, they help to reduce the risk of flooding by capturing and storing stormwater runoff during heavy rain events. This can help to prevent damage to infrastructure and property.

Additionally, infiltration basins help to improve water quality by removing pollutants and sediments from stormwater runoff. As the water infiltrates into the ground, it is naturally filtered and treated by the soil, reducing the amount of pollutants that reach nearby water bodies.

Infiltration basins also help to recharge groundwater supplies. By allowing stormwater to infiltrate into the soil, they help to replenish underground aquifers, which are important sources of drinking water. This can help to ensure a sustainable water supply for communities.

Design Considerations for Infiltration Basins

When designing an infiltration basin, several factors need to be considered to ensure its effectiveness. The size of the basin should be large enough to capture and store the anticipated volume of stormwater runoff. The depth of the basin should be sufficient to allow for infiltration without causing groundwater contamination.

The location of the infiltration basin is also important. It should be situated in an area with suitable soil conditions for infiltration, such as sandy or loamy soils. The basin should be located away from sensitive areas, such as drinking water wells or areas prone to sinkholes.

Maintenance of Infiltration Basins

Regular maintenance is essential to ensure the long-term effectiveness of infiltration basins. The basins should be inspected regularly to check for signs of erosion, sediment buildup, or vegetation overgrowth. Sediment and debris should be removed from the sedimentation ponds to prevent clogging and maintain proper functioning.

Vegetation management is also important for infiltration basins. Native plants and grasses can help to stabilize the soil, reduce erosion, and enhance infiltration. However, invasive plant species should be controlled to prevent them from outcompeting native vegetation and reducing infiltration rates.


Infiltration basins are valuable stormwater management tools that help to capture and treat rainwater runoff. They provide numerous benefits, including flood prevention, water quality improvement, and groundwater recharge. By properly designing and maintaining infiltration basins, communities can effectively manage stormwater and protect the environment.