Detention tanks are stormwater storage units that slow down the rate of water flowing from your roof into the storm drain. The size of the tank/compartment and the outlet are engineered in a way that it only allows a pre-defined volume of water flow, this ensures a steady weak flow to prevent damages. This is especially useful in areas where simultaneous water flow from multiple outlets can put a strain on council infrastructure. Detention modular tanks can also act as the water storage unit and are available in a wide range of sizes to suit all types of properties. They can also be used along with a retention tank in which case it works as a separate unit to control rainwater disposal.