Mound Systems for On-site Wastewater Treatment

Siting, Design and Construction in Ohio

Bulletin 813

How Are Mound Systems Maintained to Insure Decades of Trouble-Free Operation?

Maintenance-free wastewater treatment systems do not exist. All onsite wastewater treatment systems require at least annual inspection and maintenance. Because mound systems have mechanical pumps and small diameter laterals, residential systems require semi-annual inspection. Each inspection and maintenance takes a trained professional approximately 30 minutes to complete. For systems with great distances between pumps and the mound, it may take as long as one hour to complete the necessary inspection and maintenance.

Important inspection and maintenance steps include:

• Make sure no trees or shrubs are planted on the mound. Tree roots will clog the distribution pipes.
• Avoid sprinkler systems and irrigation on a mound. Plant ground-cover vegetation that can tolerate dry conditions, if necessary.
• Walk around the lot and look for landscape changes that can interfere with or damage the mound system.
• Walk downslope of the mound to check for signs of surfacing sewage.
• Locate and open up each inspection port to check for ponding.
• Activate the pump and check alarms.
• Open valve box at the end of each lateral to open and flush lines to remove debris that may clog holes in the small diameter pipes.
• Conduct a pressure test for each line and compare it to the initial test to check for plugging or broken pipes.

Figure 5. Valve to flush line at end of each lateral (not to scale)