Houston, We Have a Solution: When Every Acre Counts

Key Takeaways:

• A low-impact drainage approach helped manage stormwater while protecting productive acreage on a 290 MW solar project.
• Rain-on-grid HEC-RAS modeling showed how runoff moved across the site’s actual topography, reducing reliance on larger, centralized drainage facilities.
• Working with the existing terrain kept grading close to natural contours and balanced cut and fill without importing or exporting material.
• Coordinating stormwater management with the solar layout early can preserve more land for energy infrastructure.

On a 290 MW utility-scale solar project, every acre had a job to do. But one critical mission parameter was competing for space: stormwater management.

Traditional drainage approaches often direct runoff into larger conveyance or detention facilities. While effective, those features can occupy valuable acreage, increase grading and reduce the land available for solar infrastructure.

Mission control had its directive: manage runoff without sending the site plan off course. The objective was to keep more acreage working toward energy production.

Houston, we have a solution. Manage runoff at the source.

Project Engineer Kaylah Angel and the team charted a different course, developing a low-impact drainage approach that addressed stormwater closer to where it fell rather than concentrating it into larger facilities.

Using SCS Curve Number methods within a rain-on-grid HEC-RAS model, the team simulated how runoff would move across the site’s actual topography. The analysis gave the team the critical intel needed to understand drainage patterns without relying on conservative, one-size-fits-all detention sizing.

With a clearer view of the terrain, the team could fine-tune the trajectory. The design reduced acreage dedicated solely to drainage infrastructure and kept grading close to the site’s natural contours. It also balanced cut and fill on site, eliminating the need to import or export material.

The result kept two critical project priorities on the same trajectory: effective stormwater management and land optimization.

For solar developers, drainage design influences more than regulatory compliance. It can affect grading, infrastructure, construction costs, usable acreage and ultimately energy production. Bringing drainage into the site-planning conversation early helps keep those priorities aligned before the project reaches the launch pad.

Mission Debrief: How to Keep Every Acre Working

• Manage Runoff at the Source: Address stormwater closer to where it falls to reduce reliance on larger facilities.
• Work With the Terrain: Use existing topography to minimize grading and unnecessary site disturbance.
• Balance the Site: Coordinate cut and fill to reduce material movement and associated construction impacts.

When every acre contributes to project performance, stormwater management should support the site plan, not compete with it. Mission accomplished.

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