Pit Installations

Primarily due to considerations for access, safety and drainage, it is preferred that backflow prevention devices not be installed in pits. Where pit installations are proposed, however, they shall be designed:

· To be above flood control elevations;

· To be watertight with watertight manholes or access doors extending a minimum of 6 inches above grade and located to allow natural light into the pit during testing/maintenance.

· With stairways, ladders or step irons.

· For crane access for installing and removing large assemblies.

· With adequate horizontal and vertical clearances to allow access to the device.

· With a full flow screened gravity drain terminating above grade for all RPZA installations as detailed in the drainage requirements.

· With sump pumps or gravity daylight drains for all DCVA installations.

· With floors pitched to drain.

· With adequate ground cover to prevent freezing.

· With surface grading to divert runoff away from the entrance way.

· Semi-buried pits for berm installations may be necessary to satisfy gravity drainage requirements.