In a dry climate, a pond or basin is rarely about holding water for long. Detention basins catch a hard, short rain and release it slowly, retention basins hold it until it evaporates or soaks in, and process or storage ponds on industrial sites keep fluids where they belong. All of them start as excavations with exact depths, side slopes, floors and outlets, and all of them have to work the first time it rains.
Pond and basin excavation is bigger than most footing work and more sensitive to survey error. A basin that is six inches too shallow loses volume across a whole acre, and a floor that slopes the wrong way holds water against the outlet. We coordinate the earthwork partners and the testing firm, hold the grades to the plans and keep the spoil moving toward the places that need fill. In the Midland area that means working with caliche, thin soils and a rainfall pattern in which a single event can test the basin the week it is finished.
Dry country, hard rain
Midland has a hot semi-arid climate, with a mean July high of 95.8 degrees and a mean January low of 32.7. Records run from minus 11 to 116 degrees. The National Weather Service gives the city a normal annual precipitation of 13.51 inches and a normal average temperature of 65.7 degrees. Those figures describe the average, and the basin has to handle the exception: a cloudburst that delivers a large share of the year's total in a few hours.
Hard ground and fast evaporation shape the design. Floors may be lined or left unlined depending on soils, side slopes are moderate to prevent erosion and outlet structures are sized for peak flow. Because basins may sit dry for months, vegetation and erosion control are often added to keep the sides in place between storms.
Where basins connect to the rest of the site
Basins are part of a larger drainage system. The design discussion is on our page about detention and retention ponds, including outlet structures and pipes. During construction the basin often serves as a sediment trap, which ties it to erosion control and SWPPP management.
The spoil is an asset as well as a burden. When a pond is excavated at the start of a project, its soil may supply fill for pads and roads, which reduces trucking. When it must be exported, our import, export and haul-off planning covers the haul.
Survey control and staged excavation
We establish control points before the first cut and check the basin with a rover or total station as the work proceeds. The excavation is staged in lifts, with side slopes trimmed as the cut progresses and the floor finished last. Spoil is sorted by suitability so that clean soil goes to fill and the rest is stockpiled or exported.
The finished basin is checked against the plans for volume, depth, slope and outlet elevations. We produce a survey record the engineer can review and the city can inspect. The floor is trimmed to drain to the outlet, and the sides are compacted or stabilized as specified. Only then is the basin accepted for use.
Safety is part of the same record. Deep basins have steep edges and slick floors after rain, so we fence them, post warning signs and keep ladders or ramps available for the people who work in them. Water that ponds in a new basin attracts children and animals, and the owner should know that a fence is a requirement and not an option.
What can surprise a basin excavation
The first surprise is usually the ground. Caliche may require heavier equipment, and the owner should know that early; our page on excavation describes how we plan for it. Subgrade softness at the floor is also common when a basin is cut into clay-bearing pockets. Another is groundwater or a perched layer that wets the floor. If water appears, the engineer decides on dewatering, liner options or a change in depth.
The second surprise is other people's work. Utility lines cross many sites, and a basin planned over an old line can force a redesign. We use locates and potholing before the cut. Neighbors, roads and overhead lines add constraints, and we plan haul routes around them.
Drainage review and approvals
Basins are reviewed by the permit office and often by a drainage authority. The review checks volume, release rate, outlet design, side slopes and access for maintenance. Fencing and signage requirements vary. Stormwater permits apply during construction, and long-term maintenance responsibility has to be assigned.
We keep the approved plan on site and compare our as-built survey to it. If the field requires a change, such as moving an outlet to avoid a utility, the change goes through the engineer and the city before it is built. Owners who work with municipal and public works agencies are used to this process.
Scope of a basin package
The package usually includes clearing, stripping, excavation, side-slope shaping, floor grading, compaction of berms, outlet structure coordination, erosion protection and seeding or rock lining. Spoil handling and haul-off are listed separately so quantities are clear.
For larger developments the basin is only one piece. The City of Big Spring broke ground on July 9, 2026 on a $5.6 million infrastructure project for Crossroads Business Park, opening about 550 acres of development-ready land within a master plan covering over 2,500 acres. Projects of that kind need drainage designed along with the roads and utilities, and our Big Spring page describes the area.
Doing the basin early
Excavation of the basin is among the first activities on a development, since the soil is useful elsewhere and an open basin catches sediment during construction. We schedule it right after clearing and erosion control, before pads and roads. That way the basin is in place and tested when the first rain arrives.
Final shaping and outlet work come later, once the upstream grading is nearly complete, so the basin is not damaged by construction flows. Warehouse and commercial developments with large paved areas, such as warehouse sites, depend on basins that are ready before the pavement is placed, because paving increases runoff.
Send the basin plans and the drainage report
Share the grading plan, the drainage report and your schedule. We will return an excavation sequence with survey control, spoil handling and the dates the basin can be accepted and put into service.
Common Questions
How much of a pond is dug versus built up?
It depends on the grading plan. Some basins are fully excavated and some use berms. We balance the soil from the basin against fill needs on the site to reduce hauling.
Do detention basins need liners?
Not always. Many are unlined and drain or evaporate between storms. The engineer decides based on soils, groundwater and water quality requirements.
How do you control erosion on basin slopes?
Slopes are kept moderate, compacted and protected with seeding, mats or rock as specified. Outlets and inlets have energy dissipation to avoid scour.
How long does basin excavation take?
It depends on volume, ground and haul. A basin that is balanced against on-site fill moves quickly, because the soil does not leave the property. One in hard ground, or one whose spoil must be trucked away, takes longer. We give the owner a duration once we have the grading plan and the soil report.
Can a basin be used during construction?
Yes, often as a sediment trap, provided it is cleaned out and brought to final grade before turnover. We plan the sequence so sediment does not reduce the final volume.