Large precast and cast-in-place box culverts for municipal, commercial, and infrastructure projects. Stream crossings, road crossings, subdivision roads. $20K minimum, $50K-$500K+ typical.
Backwell installs large precast and cast-in-place box culverts for municipal, commercial, and infrastructure projects across Central New York. Minimum project size $20,000. Typical range $50K-$500K+. We handle stream crossings, road crossings, wetland and floodplain crossings, subdivision roads, and industrial site access for engineers, general contractors, highway departments, and site developers.
Box culverts are not driveway pipe. If you need a 15-inch round CMP under a residential driveway, we are not your contractor. If you are looking at a 6x6 precast at a subdivision stream crossing with a DEC Article 15 permit on the desk, keep reading.
Round pipe culverts work for low-flow crossings under driveways, secondary roads, and small ditches. CMP, RCP, and HDPE handle flows up to roughly 50 CFS in diameters up to 60" economically. Above that, round pipe becomes impractical.
Box culverts are specified when:
The workhorse of the industry. We install precast box sections from ACO, Contech, Oldcastle Infrastructure, and regional precasters. Sections arrive in 4, 6, or 8-foot lengths, get set with a 60-ton or 100-ton crane depending on weight per section, and joint sealed with butyl rope and external wraps per spec.
Default choice for most commercial and municipal projects because setting goes fast , 60 to 100 LF per day in good conditions , and quality control is handled at the plant. Lead times in CNY: 4 to 8 weeks for standard sizes, longer for special details.
Specified when precast won't work: unusual span-to-rise ratios, skewed crossings where precast joints would be cut at angles, special wingwalls or headwalls integrated with the barrel, or projects where crane access is restricted. We form, reinforce, and pour in place. Slower , 2 to 4 weeks of form/rebar/pour/cure time for a typical 40-foot barrel , but handles geometry precast simply can't.
For waterways that exceed single-cell capacity. Twin 8x8 or triple 10x8 configurations are common on significant stream crossings. Multi-cell installs require wider excavation footprints, more careful bedding preparation to keep all cells at matching grade, and often additional dewatering capacity.
Single-cell box culverts from 4x4 up to 12x12, multi-cell configurations for larger waterways. Below 4x4 is usually round pipe territory. Above 12x12 single cell you are generally moving into short-span bridge work , see our bridge work page for structures above that threshold.
| Size (span x rise) | Installed/LF | Typical Length | Project Total |
|---|---|---|---|
| 4x4 single cell | $650 – $950 | 30-60 ft | $25K – $60K |
| 6x4 / 6x6 single cell | $900 – $1,400 | 40-80 ft | $45K – $120K |
| 8x6 / 8x8 single cell | $1,300 – $2,100 | 40-100 ft | $75K – $220K |
| 10x8 / 10x10 single cell | $1,900 – $3,200 | 50-120 ft | $120K – $400K |
| 12x8 / 12x12 single cell | $2,800 – $4,500 | 60-150 ft | $200K – $700K |
| Twin-cell 8x8 or larger | +70-90% over single | Varies | $250K – $1M+ |
Includes excavation, Type 2 or Type 4 bedding, precast sections, joint sealing, backfill, basic erosion control. Permit fees, wingwalls, headwalls, scour protection, and traffic control are additional. Every project gets priced from plans and a site visit.
Most CNY stream crossings sit in saturated native material. Box culvert excavations 8-12 feet deep routinely hit groundwater within the first few feet. We plan dewatering at the estimate stage , wellpoint systems, sump pits with submersible pumps, or bypass pumping for live streams. Trying to place bedding in flowing water burns schedule and compromises the base.
Onondaga County clay is famously unforgiving under concrete structures. Bedding specs typically call for 12" of Type 2 select fill over geotextile, and in some cases a full undercut and replacement below the bedding to reach competent material. Skipping this step shows up as differential settlement at the joints within a few years.
Feasible in CNY winters but comes with cold-weather concrete provisions, frozen ground excavation costs, and tighter windows between weather events. We schedule most box culvert work April through November when possible.
Backwell does not pull permits , that's the engineer of record's responsibility , but we have worked with most regulatory agencies in the region and can flag red flags during the bid phase.
Box culverts on subdivision roads in Clay, Cicero, and Lysander. Replacement crossings on municipal roads in Onondaga County. Industrial site access culverts for warehouse and manufacturing projects in the I-81 and I-481 corridors. Project sizes range from single 6x6 crossings at $60K to multi-cell 10x10 installations exceeding $400K.
$20,000. Below that we are not the right fit. Typical box culvert installations run $50K to $500K+. Commercial and municipal contractor , residential driveway culverts are not our work.
Typical 60-foot single-cell precast installation: 2-4 weeks mobilization to backfill complete, assuming permits in hand and site accessible. Cast-in-place adds 2-4 weeks for forming and curing. Multi-cell installations and projects requiring extensive dewatering run longer.
No. Permits are pulled by the engineer of record or project owner. We work from approved plans and permit conditions. We can advise on constructability and flag permit issues during bidding.
Yes, with bypass pumping or temporary stream diversion. Most DEC permits require in-stream work within a specified window (typically June 15 - September 30) and require turbidity controls, coffer dams, or dewatered work areas. We build bypass plans into our schedule.
We can, but prefer April through November. Winter requires cold-weather concrete provisions, frost excavation, tighter weather windows. Most engineers schedule box culvert work for the warmer months.
Box culvert work frequently ties into bridge construction, site excavation, road construction, and underground utility installation. For budgeting context on larger site work projects, see our guide on commercial site work costs.
Backwell serves Onondaga, Oswego, Cayuga, Madison, and Oneida counties. For box culvert projects meeting our $20,000 minimum, call (315) 400-2654 to discuss plans, schedule, and site conditions. 25 five-star Google reviews.
Backwell operates alongside RenPro Property Management, a Syracuse property management company with 107+ Google reviews managing properties across Onondaga, Oswego, Cayuga, Madison, and Oneida counties. Our team also publishes property management software at RenPro.com. Read the full story on our network page.