Maintenance - Bio-Filter™ Stormwater Biofiltration System

Maintenance frequency for the AquaShield™ Bio-Filter™ will ultimately be determined by site stormwater runoff conditions and plant growth. Inspections of the trash shelf, pretreatment chamber and underdrain area can be accomplished via the two 15-inch diameter metal cover access ports. Inspections of the biomedia can be performed through the removable grates. We recommend periodic inspections following installation to determine a site-specific maintenance cycle to ensure functionality, including plant sustainability. The biofiltration chamber only requires limited media replacement to include the top 3-inch mulch layer and the top few inches of the soil filter media, being careful not to disturb the plant’s rootball or stability. Replacement biomedia is available from AquaShield™. 

We recommend that periodic system inspections be performed to determine the pollutant and trash loading characteristics. It is important that a consistent maintenance program be established for each unit. An Inspection and Maintenance Manual is furnished for each project installation to track and document system operations and maintenance needs.

A Bio-Filter™ maintenance event should first include removing the tree grate and the two access port covers to the trash shelf and pretreatment chamber. The top mulch layer in the biofiltration chamber should be removed when obvious signs of degradation, sediment, trash and/or oil accumulations are present in the upper layer of the biofiltration chamber. The 3-inch top mulch layer should be completely replaced and can be removed by shoveling or vacuuming. The top three to six inches of the underlying biomedia should be replaced at the same time. It may be necessary to replace several more inches of biomedia as warranted. Care should be taken not to damage the plant or disturb its rootball during biomedia replacement. The trash shelf, pretreatment chamber and outlet chamber can be vacuumed through the two access ports. The underdrain pipe can be vacuumed through the trash shelf (front) access port.

All inspections and maintenance activities can be performed from the surface without the need for AquaShield™ personnel to be on-site. We recommend that all materials removed during the maintenance process be handled and disposed in accordance with all applicable federal, state and local guidelines. Depending on the influent pollutant characteristics of the facility drainage area, it may be appropriate to perform Toxicity Characteristics Leaching Procedure (TCLP) analyses on representative samples of the spent filter media to ensure that the handling and disposition of materials complies with applicable environmental regulations and practices. ​