Septic Engineer in Constantia, NY

Septic design in Constantia: the short answer

Most homes along the north shore of Oneida Lake in Constantia treat their own wastewater. A septic design is the PE stamped plan that proves to the Oswego County Health Department where a new or replacement system can go on your lot, how big it has to be, and what kind of field the soil allows.

On the lake side of Route 49 the answer is usually set by two things: the 100 foot separation from the lake and the seasonal water in the low sandy ground. Upland lots north of the road tend to have more room and drier soil. Backwell coordinates the testing, the stamped design, the county submittal and the install.

Sewer or septic in Constantia

The town has worked on a north shore sewer since 2019. Its posted project summary says the town signed an intermunicipal agreement with the Village of Cleveland to treat sewage from a town sewer district of 900 to 1,100 homes in exchange for plant upgrades, and that the estimated cost roughly doubled from about $32 million to near $72 million in five years. July 2026 local reporting described the Constantia Bernhards Bay sewer project as still chasing grant money.

Until a main is built and you connect, county septic rules apply to any repair or replacement.

How a septic design works in Constantia

1. Send the address and a few photos. Use the form below. Estimate in 1 hour.
2. Confirm the lot needs septic. Confirm there is no sewer main at the road. Along the north shore, the planned Constantia Bernhards Bay district has not replaced private systems yet, so a failed system gets a septic replacement design.
3. Deep hole and perc tests. At least one test hole six feet deep at the leaching area and at least two perc tests per system, per Appendix 75-A. Close to the lake the pit often shows wet sand within a couple of feet of grade; on higher ground north of Route 49 the sand can run deep and dry.
4. Design and stamp. Designs are prepared and stamped by a New York licensed Professional Engineer (PE), sized at a minimum of 110 gallons per day per bedroom for a new house.
5. Oswego County plan review. Four sets of plans and the plan review fee go to the Oswego County Health Department, Environmental Health Division, 70 Bunner St., Oswego. The department engineer sends three sets back with a letter of approval or rejection, and a copy of that letter goes to you and to the Town of Constantia code enforcement officer.
6. Building permit and install. With the approval letter in hand, the building permit is pulled through the Town of Constantia code enforcement office. Backwell coordinates the excavation, tank, distribution box and absorption area and builds them to the approved plan.
7. Final paperwork. For an alternative system such as a raised bed, mound or sand filter, state rule 10 NYCRR 75.5 has a design professional supervise construction and certify to the health department that it matches the approved plans.

Soils and seasonal water around Constantia

Constantia sits on the sandy lake plain left by Glacial Lake Iroquois. Upland soils include Colonie loamy sand and Elnora loamy fine sand; the low ground near the shore and along Scriba Creek carries Sun and Stockholm soils, with Scriba fine sandy loam where a firm layer perches water. The USDA puts the top of the Scriba fragipan 12 to 18 inches down and Stockholm's perched water table at 0 to 12 inches.

For a septic field that splits the town in two. A camp lot on Colonie sand near the road may take a conventional or shallow trench field. A lot on Scriba or Stockholm ground near the water usually cannot meet the 4 feet of useable soil a conventional field needs, so the design goes up: a raised bed or a mound built on clean sand, pressure dosed.

What the health department checks

Oswego County reviews septic plans itself, at its Environmental Health Division in Oswego. The state sets the floor in Appendix 75-A; a local health department may adopt stricter standards, but not looser ones without a state waiver. On a lot in Constantia the review comes down to a handful of measured items:

• 100 feet from an absorption field, raised bed or mound to a stream, lake, watercourse or wetland, measured to the mean high water mark, and 50 feet from the tank.
• Conventional trench field: at least 4 feet of useable soil above rock, tight soil and the high seasonal groundwater, with the highest groundwater at least 2 feet below the trench bottom.
• No absorption system in ground lower than the 10 year flood level, and no field on slopes steeper than 15 percent.
• 100 feet from an absorption field to a well or suction line, 200 feet if the field sits upgrade and in the drainage path to the well, and 50 feet from the septic tank to a well.

Common Constantia site problems and the design fix

Narrow lake lot, well and lake both close

Long, narrow lots with a well near the house. The field stays 100 feet from the lake and 100 from the well, 200 if upgrade in its drainage path, so it often lands on the road side with a pump.

Seasonal camp turning into a year round house

A camp built with a small tank and a short field was never sized for full time use. New construction is designed at 110 gallons per day per bedroom at minimum, and older fixtures push the number to 130 or 150. Converting a camp usually means a new tank and a larger field, and the bedroom count on the plans sets the size.

What it costs

Published county fees, effective January 1, 2026: $125 for the Oswego County Health Department to review plans for one home and $250 for a commercial system, a category the county applies to businesses and rentals. Selling a house? The county lists a 4 day septic dye test with written results at $230.

Design and install are priced together in writing for your lot. A north shore lot that needs a mound with a pump chamber and imported sand costs more than an upland lot with a gravity trench field, and the written price shows each line.

Grant money: Oswego County runs the state Septic System Replacement Fund. Its application says eligible projects can be reimbursed up to 50 percent with a $10,000 maximum, design costs at 50 percent up to $3,000, and every replacement must be county approved, engineer designed and covered by a local building permit. The state priority waters for Oswego County are the central and eastern Lake Ontario shoreline and the upper Little Sandy Creek and its tributaries.

Timeline

Spring shows the true north shore water table. After testing and design, four sets go to the county with the $125 fee.

Raised systems built with fill that is not clean granular sand or sandy loam must settle for at least six months including a freeze and thaw cycle before the trenches go in. Mound sand goes in without that wait, which is one reason mounds are common on wet lake lots. The written price includes the schedule.

Sources

• Oswego County Health Department: Septic Plan Review
• Oswego County Health Department: Water Supply Protection and Septic Plan Review
• Oswego County Health Department: Plan Review Fee Schedule, effective 1/1/2026
• Oswego County Health Department: Fee Schedule for Environmental Health Services, 1/1/2026
• Oswego County Community Development, Tourism and Planning: Septic System Replacement Grant Application
• NYS EFC: Septic System Replacement Fund Priority Waterbody List
• 10 NYCRR Appendix 75-A.4: Soil and site appraisal (Table 2 separation distances)
• 10 NYCRR Appendix 75-A.8: Conventional subsurface treatment systems
• 10 NYCRR Appendix 75-A.9: Alternative systems (raised, mound, sand filter)
• 10 NYCRR Appendix 75-A.3: Sewage flows
• 10 NYCRR Section 75.5: Minimum standards, design professional, alternative system approval
• Town of Constantia: Waste Water Project Summary
• CNY Signal: Constantia sewer project chases grants (July 2026)
• NYSDEC ENB: Southern Oswego County Regional Interceptor Sewer
• USDA NRCS Official Series Description: Scriba
• USDA NRCS Official Series Description: Stockholm
• USDA NRCS Official Series Description: Colonie
• USDA NRCS Official Series Description: Sun

Rules and fees as published by the agencies above when this page was written; they can change. The approved plan for your lot controls.