Septic Engineer in DeWitt, NY
North DeWitt is sewered. South of Woodchuck Hill and Nottingham Roads the town plan says much of it is not. Testing, PE stamped designs and the county submittal.
Fees. Process. Answers.
Septic design for DeWitt, NY, from soil test to county approval.
DeWitt's 2017 Comprehensive Plan Update says the area generally south of Woodchuck Hill and Nottingham Roads, except the Doubletree neighborhood, did not have public sewage disposal, along with parts of the neighborhoods east and west of Maple Drive and an area east of I-481 from the railroad to the Thruway.
The town plan says expansion of water and sewer districts will not occur in any significant way, and that lots outside utility districts should be large enough for on site sewage disposal. The Jamesville sewer district covers the hamlet.
The Onondaga Escarpment. Southern DeWitt has limestone close to the surface and karst topography, so the depth of usable soil over rock decides the system type, and the county can require more separation to bedrock over aquifers.
The Onondaga County Health Department, Bureau of Public Health Engineering, at 421 Montgomery Street in Syracuse. DeWitt Codes issues the building permit.
Designs are prepared and stamped by a New York licensed Professional Engineer (PE).
Use the form. Estimate in 1 hour.
Septic engineer in DeWitt, NY: what it is and who needs one
DeWitt is mostly suburban, but its own comprehensive plan says the south end of town never got public sewer. A septic engineer there tests the soil, designs to Appendix 75-A, and gets approval from the Onondaga County Health Department. DeWitt adds a twist the flat towns do not have: the Onondaga Escarpment runs across the south of town with limestone, karst and quarries.
Backwell coordinates testing, design, the submittal and the install. Designs are prepared and stamped by a New York licensed Professional Engineer (PE).
Where DeWitt's plan says sewer stops
DeWitt is in the county Consolidated Sanitary District, and the county's Meadowbrook-Limestone plant in Kirkville serves sections of DeWitt, Manlius, Pompey and Syracuse. The town's 2017 Comprehensive Plan Update is specific about the gaps:
- Except for the Doubletree neighborhood in the southwest corner, the area generally south of Woodchuck Hill and Nottingham Roads did not have public sewage disposal as of 2002.
- Significant parts of the neighborhoods east and west of Maple Drive are without public sewer.
- So is an area east of I-481 from the railroad to the Thruway.
The plan says the Jamesville sewer district and new sewers in the hamlet partly addressed this, that development outside utility districts should be low density on lots large enough for on site systems, and that sewer expansion will not occur in any significant way. In other words, septic is the long term plan for those parts of DeWitt.
Soils in DeWitt and the system they point to
North DeWitt is lowland: Niagara and Minoa soils on old lake and delta deposits, plus a lot of urban and quarried land. The south end climbs the escarpment onto Honeoye till, with Benson soils where limestone is 10 to 20 inches down.
| Soil series | Share of land | What it is (USDA) | What it usually means for the design |
|---|---|---|---|
| Honeoye | 15% | very deep, well drained loamy glacial till | Often deep enough for a conventional trench field. The perc rate and the 6 foot test pit still decide it. |
| Niagara | 12% | very deep, somewhat poorly drained silty lake sediments | High seasonal water and slow perc. Raised beds and mounds are common here. |
| Benson | 5% | shallow soil with limestone or calcareous shale at 10 to 20 inches | Rock this close to the surface rules out conventional trenches and a mound (mounds need 2 feet to rock). A raised bed needs at least 1 foot of usable native soil. |
| Minoa | 4% | very deep, somewhat poorly drained deltaic sediments | The series is named for Minoa. Fine sand with high spring water, a classic raised bed or mound soil. |
| Palmyra | 3% | very deep, well drained gravelly outwash over stratified sand and gravel | Drains well, sometimes too well. Soil faster than 1 minute per inch is not suitable as is under 75-A. |
| Cazenovia | 3% | very deep, moderately well drained loamy till | Usually enough soil. Watch for spring water perched on denser till. |
USDA septic absorption field ratings, the Town of DeWitt boundary: very limited 89 percent, somewhat limited 11 percent of rated land. Leading limits: shallow seasonal water, slow water movement, fast seepage in the bottom layer.
About 89 percent of DeWitt's rated land is very limited for conventional fields. Shallow seasonal water leads, then slow water movement, seepage in the bottom layer and depth to bedrock. South of Woodchuck Hill the question is usually rock. Honeoye till can give a conventional or shallow trench field. Where Benson soils show limestone near the surface, a raised bed needs at least 1 foot of usable native soil, and a mound needs 2 feet to rock. Where the pit shows creviced limestone, the county guidelines note 4 feet of separation to bedrock may be required to protect the aquifer.
Karst, creeks and wetlands in DeWitt
The town plan describes the Onondaga Escarpment, with limestone cliffs and karst topography, running east to west across southern DeWitt through White Lake, Clark Reservation State Park and Ram's Gulch, and quarrying across a large swath of the south. Creviced rock is exactly what onsite rules are wary of. Appendix 75-A says highest groundwater must be 2 feet below the trench bottom, and the county can require more separation to bedrock over drinking water aquifers.
The north end has the opposite problem. DeWitt has about 2,700 acres of DEC regulated wetland, with floodplains along Butternut Creek and Ley Creek, and the North Branch of Ley Creek floods periodically. Fields stay 100 feet from those wetlands and creeks and above the 100 year flood level.
How a septic design in DeWitt works
- Send the address. Use the form. Estimate in 1 hour.
- Confirm sewer or septic. If a public sewer can serve the lot, you do not need a septic design.
- Perc holes and a deep test pit. At least two staked perc holes in the design area (30 inches deep for a conventional system) and a test pit logged to 6 feet for mottling, water and rock.
- Stamped design. A scaled plan with the tax map number, nearby wells, elevations and system details. Designs are prepared and stamped by a New York licensed Professional Engineer (PE).
- County submittal. Plan and fee go to the Bureau of Public Health Engineering, 421 Montgomery Street, Syracuse: 3 plan copies outside the lake watersheds. Once approved, a copy goes to the town.
- Town permit. DeWitt Planning and Zoning, Codes Enforcement, at Town Hall, 5400 Butternut Drive. The town says plumbing inspections are handled by Onondaga County and inspections need 24 hours notice.
- Install and inspection. County inspection on 24 hours notice. Inside plumbing is done by a plumber licensed through Onondaga County Plumbing Control, and fill systems get the engineer's fill certification first.
What it costs
The county fee schedule sets the health department side for a lot under 1,000 gallons per day: $310 full application, $186 redesigned project, $62 amended project or revised plan review, $93 site investigation, $62 repair inspection. The fee is paid with the plans and covers the county's review and construction inspection. Testing, design and install are priced in writing.
What the health department checks
The county reviews the plan against New York's Appendix 75-A and its own design guidelines. In southern DeWitt the checks that matter most are rock depth and the 100 foot well distance on larger wooded lots. In the north, it is the wetland setback and flood elevation.
- Flow and tank. 110 gallons per day per bedroom for new construction. Tank size follows the bedroom count.
- Usable soil. Conventional: 4 feet over rock, clay or high water, with water 2 feet below the trench bottom. Shallow trench: 2 to 4 feet. Raised bed: 1 to 2 feet, water 1 foot down. Mound: water 1 foot down, rock 2 feet down, native perc faster than 120 minutes per inch, slope under 12 percent.
- Separations. Field, raised bed or mound: 100 feet to wells (200 if upgrade in the drainage path), 100 feet to water and wetlands, 20 to the house, 10 to the lot line, measured from the toe of any fill. Tank: 50 feet to wells and water.
- Site limits. No field over 15 percent slope or below the 10 year flood level, system above the 100 year flood level, no soil faster than 1 minute per inch unless modified, and 50 percent expansion area where possible.
Common DeWitt problems and how the design handles them
Wooded lot south of Woodchuck Hill
The problem: Rock and roots. The county guidelines want heavily wooded sites labeled, with trees in the system area removed for installation.
How the design handles it: The test pit and perc holes go where the field can realistically be cleared, and the plan notes the clearing so there are no surprises at install.
Limestone with cracks
The problem: Karst and creviced bedrock can carry effluent without treatment. Appendix 75-A and county rules both call for more separation over aquifers.
How the design handles it: The PE designs enough usable soil or fill over the rock, and if a site cannot give that, says so before you spend more.
Building lot in an unsewered pocket
The problem: The town plan says lots outside utility districts should be large enough for on site sewage disposal.
How the design handles it: A feasibility test before purchase shows whether the lot can hold a field plus 50 percent replacement area and the setbacks.
Timeline
Escarpment rock depth can be tested any time the ground is open. Lots on the lowland near Butternut and Ley creeks should be tested in spring. A raised bed adds the county's fill certification step before the field goes in.
Sources
Soil shares and ratings come from the USDA NRCS soil survey (SSURGO) for Onondaga County, summarized for the Town of DeWitt boundary. Regulations and fees as published by the agencies below; they can change.
- Onondaga County Health Department, Septic Systems (Bureau of Public Health Engineering)
- Onondaga County Environmental Health fee schedule
- Onondaga County Design Guidelines for Individual Sewage Systems
- Onondaga County Health Department Fill Certification Form
- NYS DOH 10 NYCRR Appendix 75-A, Wastewater Treatment Standards, Residential Onsite Systems
- NYS DOH fact sheet: Need for Licensed Design Professionals, Residential OWTS
- Onondaga County WEP, Consolidated Sanitary District service area
- Onondaga County WEP Plumbing Control
- Onondaga County WEP, Meadowbrook-Limestone WWTP
- USDA NRCS Web Soil Survey, Onondaga County (NY067)
- USDA NRCS Soil Data Access (SSURGO), septic tank absorption field ratings
- Town of DeWitt Comprehensive Plan 2017 Update
- Town of DeWitt permits
- USDA Official Series Description: Honeoye
- USDA Official Series Description: Niagara
- USDA Official Series Description: Benson
- USDA Official Series Description: Minoa
- USDA Official Series Description: Palmyra
- USDA Official Series Description: Cazenovia
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