Solar sites span hundreds of acres with varied topography, unpredictable drainage patterns and soil conditions ranging from sand and gravel to silty clays and rich organic topsoil. Many are located near regulated streams and wetlands, which increases regulatory risk and scrutiny. These factors make environmental risk management a critical part of early project development — not just during construction.
The most effective approach involves identifying risks early into the design phase of a project. This allows design and construction teams to integrate erosion control measures, develop practical mitigation strategies and avoid last-minute changes that can delay permitting or trigger unaccounted for environmental regulations.
Under the Clean Water Act, construction sites that disturb more than 1 acre of land must comply with the National Pollutant Discharge Elimination System (NPDES). This federal regulation, managed at the state level, requires coverage under a Construction General Permit; a core component of that permit is the Stormwater Pollution Prevention Plan (SWPPP). The SWPPP outlines how erosion and sediment will be controlled, how stormwater will be managed, and what inspection and maintenance procedures will be followed throughout construction.
Evolving Practices in Solar Development
Moved away from relying solely on downstream sediment basins, many solar developers now prioritize and emphasize upstream erosion prevention — such as pre-seeding a project prior to mobilization and mulching and stabilizing disturbed areas while construction activities are ongoing — to minimize sediment transport across large sites. These measures not only reduce erosion but also help avoid delays due to compliance issues or failed inspections.
Environmental risk for solar projects also includes legal and financial liabilities. Violations of NPDES requirements can result in enforcement actions from the U.S. Environmental Protection Agency and the Department of Justice. Consent decrees — which may impose long-term obligations like audits, reporting and financial penalties — recently have been issued to solar developers that have been serial offenders of the Clean Water Act. More commonly, civil lawsuits from adjacent landowners, claiming property damage due to runoff or erosion, are becoming increasingly common.
Long-Term Impacts
Public perception also is a factor in determining project viability. Negative press, community opposition or shareholder concern can damage a company’s reputation and impact future development opportunities. Poor environmental performance on one site may influence agency decisions and requirements or landowner support on the next.
Environmental protection on solar construction sites is typically achieved through a combination of erosion and sediment control measures, commonly referred to as Best Management Practices (BMPs). Erosion control BMPs are designed to prevent soil from being dislodged, often through vegetation, mulching or ground cover. Sediment control BMPs, such as silt fences or check dams, reduce stormwater velocity and trap soil that has already been dislodged.
Many BMPs are temporary and installed during active construction, while others become part of the site’s permanent stabilization plan. The timing and placement of these measures are critical and should reflect the site’s specific conditions, including soil type, drainage area size, topography, and the location of graded or disturbed land.
Importance of Early Collaboration
Effective erosion and sediment control design depends on coordination among civil engineers, environmental planners and construction teams. With early collaboration, risks can be addressed proactively, rather than through last-minute responses that may not align with project goals or regulatory timelines.
Solar construction projects succeed when environmental concerns are addressed at the start, not just when problems arise. Integrated planning helps reduce permitting delays, limits compliance risks and supports a smoother construction process. More importantly, it fosters trust with landowners, regulators and local communities — trust that will matter long after construction is complete.
