Underground
Catch basin, drywell, manhole, and vaults
Maintenance is needed if you see these signs
• The facility drains slowly after a rain storm.
• Leaves, trash and other debris slow or stop outflow or filtration.
• There is more than ¼ - ½ inch of sediment on the cartridges.
Confined space warning for underground facilities
Due to potential dangers, only trained and certified persons should enter confined spaces. These are defined as:
• Large enough that an individual could fully enter the space and work.
• Having limited or restricted entry or exit.
• Not primarily designed for human occupancy.
For more information visit Washington State Labor & Industries confined spaces rule.
Checklists for maintenance and recognizing and fixing problems (PDF files)
• Catch basin
• Drywell
• Manhole
• Vault - stormwater filter
• Vault - vortex sedimentation
• Vault - closed detention system
Facility Elements
• Field inlet
• Flow control structure/flow restrictor
• Access road
• Fence, gates, signs