Legacy Excavation LLC

Title 5 (310 CMR 15.00) governs on-site systems in Plymouth, requiring a permit from the Plymouth Board of Health and a design stamped by a registered sanitarian or professional engineer, built by a licensed installer. Before most transfers, a Title 5 inspection by a licensed inspector is required on septic-served properties, and given how much of Plymouth is on septic, this comes up constantly. Near the town's coastal ponds, the Eel River, and the bays, MassDEP's 2023 watershed-permit framework can require a nitrogen-reducing Innovative/Alternative (I/A) system, plus a Conservation Commission filing for wetland-buffer work.

Plymouth septic pricing sits in the South Shore mid-to-upper range, driven by coastal access and nitrogen rules. A Title 5 inspection at sale typically runs a few hundred dollars to about $1,000, and tank pumping a few hundred dollars. A full conventional replacement on sandy Plymouth soil commonly runs roughly $20,000–$35,000. The key local driver is nitrogen: in designated nitrogen-sensitive areas near the ponds and bays, a required I/A system pushes costs to $30,000 or more, with ongoing monitoring and maintenance the system needs.

Massachusetts requires a written contract and a Home Improvement Contractor registration for most residential septic installation & service work; ask for the registration number and check it before paying a deposit.

More on permits, costs, rebates and common questions, plus every other septic installation & service contractor serving the town, on the Septic Services in Plymouth page.