Water in Natrona County shows up all at once or not at all. A cloudburst on a paved yard, a spring melt running off a hillside, or a thaw on top of frozen ground can put more water on a site in an hour than the plan assumed for a day. We build storm sewer, inlets, culverts, swales and detention to handle that, and we build them so the pavement and slabs above them stay where they were poured.
Casper sits on the North Platte River at 5,150 feet, and the ground rises toward Casper Mountain, which reaches 8,130 feet roughly 3,000 feet above town. Runoff has somewhere to go, but not always where an owner wants it. Drainage that is sized right on paper still fails if the outlet is blocked, the grade is off by an inch, or a trench was backfilled with the wrong material.
The public work is a good example of the scale of the problem. WYDOT awarded the Poplar Street reconstruction between Collins Street and the North Platte River bridge at $12.79 million, with new road surface and storm and sanitary sewer and utility upgrades, and a follow-on reconstruction between CY Avenue and Collins Drive carries a contract completion date of September 30, 2028. Private sites tie into that infrastructure, and we plan our connections around it.
Freeze-thaw is the quiet enemy. The City of Casper lists a 3,000 air freezing index and severe weathering in its climatic criteria, which means pipe bedding, inlet frames, curb lines and pavement edges all see repeated cycles of ice and water. A drainage detail that works in a mild climate cracks here. We specify and install with that in mind and push back on drawings that ignore it.
Close to the river and low ground, groundwater can be shallow. Along Poplar Street, the state has been replacing storm and sanitary lines as part of its road work, and nearby Poplar Street corridor owners feel the disruption while it happens. We schedule private tie-ins around detours and closures and keep owners informed instead of surprising them.
Our drainage scope covers storm sewer mains and laterals, inlets and manholes, culverts, trench drains at dock and door locations, swales, detention basins and outlet structures. We shoot grades as we lay pipe, bed and compact in lifts, and test and document before backfill is closed. Rim elevations and inlet grates get set to final paving grade so there are no low spots in the finished lot.
It starts with earthwork, and the same crews handle the cut that makes a detention basin work. Our mass grading work sets the basin and swale lines, and the finished drainage feeds directly into parking lot construction, where an inch of grade error shows up as a puddle for ten years.
The City of Casper lists the 2024 International Codes with amendments in Title 15, and commercial permits there often need engineered building and site plan drawings and Planning and Zoning approval. A drainage design is part of that submittal, and plan review covers engineering reports and specifications. Expect comments, and expect to answer them before the permit is issued.
Wyoming has no single statewide building code, since cities and counties adopt and enforce their own. That matters on a drainage job because the discharge point may sit in a different jurisdiction from the building. We confirm who reviews the plan, who inspects the pipe and who accepts the outlet before we price, and we line that up through permitting and entitlements so inspection does not become the critical path.
Drainage is the trade that every other trade depends on. Foundations need positive drainage away from the footing. Floors need dry subgrade. Truck courts need a slope that sheds water without icing. On busy industrial sites, our truck courts and dock aprons work is only as good as the inlets and grades we set beneath it.
We also coordinate with the utility contractors who share the trench corridor. A storm line crossing a water main or a gas line is a conflict that is cheap to solve on paper and expensive to solve with a backhoe, so we resolve it before excavation starts, and we keep the survey of installed lines for the owner.
Deep trench work gets shoring or sloping to the standard, daily competent-person inspections and clear spoil placement. In a town where wind and cold shut work down for a day at a time, we also keep walkways and access points clear of ice and snow and keep open trenches covered or barricaded overnight. A wide open trench with a snow drift on it is a hazard nobody sees until it is too late.
When we work in the public right of way, traffic control is planned with the city or the state before the first cut. We keep one lane open where we can, phase tie-ins to the shortest possible closure and restore pavement to the standard the agency requires. Owners and engineers in the government and public sector will recognize the routine, and private owners benefit from the same discipline.
Send the grading plan, the drainage report and the location of the outlet. We will review the pipe and basin scope, flag permit and tie-in issues and give you a schedule that respects frost and traffic. Call or use the quote form to start.
That depends on the impervious area you add, the release rate the reviewer allows and the soil conditions at the basin location. The engineer of record sizes it; we build it to the grade and compaction the design calls for. What we add is practical experience on where basins freeze up, where silt collects and what maintenance access the owner will need.
Frozen ground sheds water instead of absorbing it, so a thaw can send a lot of runoff to a lot of pavement at once. Inlets and culverts have to stay clear of ice, which is why we set inlet frames, grates and outlet structures with maintenance access in mind. We also avoid winter backfill of pipe trenches unless the material is unfrozen and can be compacted.
Often yes, but the city or the state has to approve it. Poplar Street shows how active the public work can be, with new storm and sanitary sewer in the road. We confirm the tie-in location, the permit holder and the inspection requirements early, because a closed street and a missing permit can stall a job for weeks.
On a commercial site, drainage is usually part of the engineered site plan reviewed with the building permit, and an issued City of Casper permit is good for 180 days. Right of way work and work outside city limits can carry their own approvals. We map all of that before we mobilize.
The owner does. We hand over as-built grades, outlet details and a short maintenance note covering silt removal and clearing the outlet. A basin with no maintenance plan turns into a pond with a fence around it, so we write the plan before we leave.