Riverhead and Southold Cesspool Replacement: Grants and Maintenance Help
On the North Fork, the main money for a cesspool replacement is the Suffolk County and New York State grants. Neither Riverhead nor Southold is on the county's list of towns offering their own septic rebate. If your home is in the Peconic Estuary's groundwater contributing area, an extra maintenance grant can help once the system is in.
Quick facts. Grants: county SIP up to $20,000 plus state SSRP up to 75% of eligible costs, capped at $25,000. Town rebate: none listed by the county for Riverhead or Southold. Maintenance: county SIP funds the first 3 years, and the Peconic Estuary grant can reimburse up to $500 a year after that, in its contributing area.
County and state grants
Riverhead and Southold homeowners apply through the county like everyone else in Suffolk. The Septic Improvement Program pays up to $20,000, straight to an installer on the county's approved list, after the system is installed and inspected. The state Septic System Replacement Program pays up to 75% of eligible costs, capped at $25,000, to the installer or back to you. You must be awarded the grant before installation. Applications with a documented failure come first, then homes in the county's priority areas, which include parcels within 1,000 feet of an enclosed water body. The application guide walks through every step.
The Peconic Estuary maintenance grant
An I/A system needs a professional maintenance contract every year. The county grant pays for the first 3 years. After that, Suffolk County runs a program funded by the Peconic Estuary Partnership that reimburses homeowners in the Peconic Estuary groundwater contributing area up to $500 a year when they renew an I/A maintenance contract. You must renew every year to keep getting it, and funding is limited. The county estimates maintenance contracts at about $300 to $600 a year, so this can cover most or all of it.
Southold's water quality fund
Southold's Town Code lets the Town spend up to 20% of its Community Preservation Fund revenue each year on water quality projects. The code says a Town Board rebate or incentive program for upgrading septic systems or cesspools would count as one of those projects. The county's grant page doesn't list a Southold septic rebate, though, and we could not find one on the Town's site. Ask the Town whether one is open before you count on it.
Riverhead
We did not find a Town of Riverhead septic rebate on any official page, and the county doesn't list one. Riverhead homeowners should plan around the county and state grants, plus the Peconic Estuary maintenance grant if the property is in its contributing area. Septic grant questions go to the Suffolk County Department of Health Services at 631-852-5811.
Before you hire
- Make sure the installer is on the county's SIP Approved Installer List, or the county grant can't pay them.
- Ask whether your lot is near wetlands or surface water. The county says wetlands permits from the town, village or the New York State DEC may be needed.
- Ask the installer what the yearly maintenance contract will cost after year 3.
Replacing a cesspool in Riverhead or Southold? Compare quotes from up to 3 independent local installers.
Get up to 3 installer quotesRelated guides
- What an I/A system costs and how the grants stack
- How to apply for the county and state grants, step by step
- Cesspool rules: replacements, renovations, new homes and selling
Other town guides
Sources
We checked every grant amount, rule and cost on this page against these official pages on November 10, 2026. Grant rules and funding change, so confirm with Suffolk County or your town before you rely on them.
- Suffolk County: Septic Improvement Program information (septic grants)
- Suffolk County: Septic Improvement Program FAQ (April 2026)
- NYS DEC: State Septic System Replacement Fund outline and summary
- Peconic Estuary Partnership: I/A OWTS Maintenance Grant
- Peconic Estuary Partnership: Upgrade Your Septic System
- Suffolk County DHS: What Homeowners Should Know About I/A OWTS (May 2026)
- Town of Southold Code Chapter 17, Article V: Water Quality Improvement