Septic Engineer in Oneida, NY

Oneida septic design in two sentences

Most of the City of Oneida drains to the city's own treatment plant, but Oneida is a 22 square mile city and a good share of that land is rural, so private septic still matters at the edges. Where a lot has no sewer, Backwell runs the soil tests, coordinates a stamped design, files the permit and installs the system. Designs are prepared and stamped by a New York licensed Professional Engineer (PE).

The city sewer and where it stops

The City of Oneida runs the largest wastewater treatment plant in Madison County, at 387 Harden Street. It is designed for 4.5 million gallons a day with a 10 MGD peak, and it discharges treated water to Oneida Creek. A small share gets tertiary treatment and is reused for summer irrigation at Turning Stone Resort.

The city's plant page does not map its service area, so we do not guess which outer parcels are sewered. The test is simple: if there is no lateral, you need a septic design. Bennetts Corners, at Peterboro and Middle Roads in the southeast part of the city, and the roads that climb from the Oneida Creek valley are where most of those lots sit.

Oneida soils: rock, clay and a few good gravels

USDA soil data for a sample area around Oneida puts these series at the top: Lairdsville, Cazenovia, Schoharie, Honeoye, Arkport and Lima. About 77 percent of that sample area is rated Very limited for septic absorption fields. Three of those soils behave very differently:

• Lairdsville is moderately deep, with bedrock at 20 to 40 inches and slow water movement in the subsoil. The series was first described in Madison County in 1955. With rock that shallow, Appendix 75-A's 4 feet of usable soil under a conventional field is out of reach.
• Schoharie is clayey lake sediment, moderately well drained, with conductivity running low to moderately high. Clay lots perc slowly and some fail outright.
• Arkport is well drained sandy ground with high conductivity throughout. It percs fast, which is easy to pass but needs care so effluent gets treated before it reaches groundwater.

Cazenovia and Lima soils, both moderately well drained limy tills, fill much of the rest. The deep hole decides which of these you have, and on Oneida's mixed ground two lots on the same road can land on different systems.

Matching the system to an Oneida lot

• Four feet or more of usable soil: a conventional trench system. Common on the Arkport and better Honeoye ground.
• Two to four feet: shallow absorption trenches. Typical where Lairdsville rock sits near 3 feet.
• One to two feet over rock or a tight layer: a raised system, with at least 2 feet of fill that percs at 5 to 30 minutes per inch.
• Groundwater at least 1 foot down and rock at least 2 feet down: a mound, with at least 24 inches of approved sand over the stone, where native soil percs faster than 120 minutes per inch.

See shallow bedrock septic design and clay soil septic design for how each case is drawn.

Step by step in the City of Oneida

1. Send the address. Estimate in 1 hour.
2. Deep hole. At least one pit at least 6 feet deep in or beside the field area, unless rock stops it first, which on Lairdsville ground is the finding.
3. Perc tests. At least two per system. Madison County Public Health lists observing perc and deep hole tests among its services.
4. Design. Sized at 110 gallons per day per bedroom, with a 1,000 gallon tank minimum for 1 to 3 bedrooms.
5. Permit. The City of Oneida code office at City Hall, 109 N. Main Street, handles the local permit. Alternative designs also go to Madison County Public Health in Wampsville.
6. Install and inspect. Backwell installs to the approved plan.

What it costs

The published county number is small: Madison County Public Health charges $125 per lot to review and inspect an alternative system, with at least 2 copies of the engineer's design and site plan. The construction cost depends on which of Oneida's soils you have. A trench in Arkport sand and a mound over Lairdsville rock are not the same job, so we do not quote a range we cannot back up. Send the address and you get a written price in 1 hour.

The county's septic replacement grant does not reach Oneida. It covers only properties within 250 feet of Cazenovia Lake, its tributaries, or parts of Canastota Creek in the Town of Lincoln.

What reviewers look at

• Usable soil depth from the test pit, with highest groundwater at least 2 feet below the trench bottom
• Fields, raised systems and mounds 100 feet from any well and 100 feet from a stream, lake or wetland. Oneida Creek and its side streams matter here
• No conventional field below the 10 year flood level or on slopes over 15 percent
• For alternative systems, the county form asks why the alternate design is needed, the soil description, depth to water table and the date it was found

Timeline

The tests take a day. Alternative designs need to reach the county at least 30 days before construction. A raised system with fill that must settle six months through a freeze and thaw adds time, unless the fill is granular sand or sandy loam compacted in lifts. Installation is days of machine time.

Sources

• City of Oneida, wastewater treatment plant
• City of Oneida, code enforcement
• Oneida, New York (Wikipedia)
• NYS DOH, 10 NYCRR Appendix 75-A
• Madison County Public Health, water and septic individual systems
• Madison County, alternative household wastewater treatment system application
• Madison County, Septic System Replacement Fund
• USDA NRCS Web Soil Survey and Soil Data Access (Madison County, NY053)
• USDA NRCS, Lairdsville series
• USDA NRCS, Schoharie series
• USDA NRCS, Arkport series
• USDA NRCS, Cazenovia series