Underground stormwater assets are used in areas where there is limited space for large aboveground ponds. Built for capacity, these underground systems, or vaults, can hold hundreds of thousands of gallons of runoff, depending on the needs of the site. Like most stormwater BMPs, underground vaults should be used in conjunction with other BMPs, especially ones intended for treatment of stormwater.
Underground stormwater vaults have many benefits and are built with engineered valves to release a measured amount of stormwater. These systems can be installed quickly as they are prefabricated modular systems and last for 50 years or more if properly maintained.
Some benefits of underground stormwater vaults include:
Because they are hidden underground, many property owners forget about these systems or don’t know they exist. Like all stormwater assets, vaults must be properly maintained to ensure full function and extended life.
To properly inspect these assets, a confined space entry certification is required. Inspectors of the system will test the contained water and measure water quality and debris. Maintenance of these systems can include removing siltation and surface debris by industrial vacuumation and skimming as well as removal