“A Hard Rains A-Gonna Fall” – Utility-Scale Solar Projects Creating Significant Stormwater Issues

Posted on April 9, 2019 by Mark R. Sussman

With apologies to Bob Dylan for taking the name of his song out of context, hard rains are going to fall, and some developers of utility-scale solar projects seem to have underestimated the damage that such rains can cause.  Over the past several years, a number of large scale solar projects in Connecticut have discharged significant amounts of sediment into wetlands and watercourses, harmed down-gradient property owners, and posed a threat to habitat essential to threatened or endangered species.  These projects have violated stormwater permitting requirements, resulting in the issuance of cease and desist orders, the imposition of civil penalties and remediation requirements, and triggering justifiable public opposition to renewable energy projects.

Utility-scale solar projects in Connecticut generally range from 10 to 20 megawatts (MW).  These projects can disturb upwards of 100 acres of land.  Usually the site selection process for these projects focuses on the ability to interconnect to the power grid, land availability, and cost.  Stormwater management issues have been a secondary concern, typically addressed in the first instance by conceptual, high level plans, rather than through site-specific soils investigations, detailed grading plans, and rigorous stormwater design calculations and analysis. 

In Connecticut, utility-scale solar projects must first be approved by the Connecticut Siting Council.  In December 2017, the Council denied an application to site a 50 MW project that would have disturbed 270 acres.  The Council denied the application, without prejudice, in large part because the application did not contain sufficiently detailed information regarding grading, and erosion and stormwater control.  The Council was concerned about stormwater management and sedimentation impacts to wetlands and watercourses that were in close proximity to the limits of disturbance and the resulting detrimental effect on water quality.

Once a solar project is approved, the developer must apply to the Connecticut Department of Energy and Environmental Protection (“DEEP”) for the General Permit for the discharge of Stormwater from Construction Activities or for an individual stormwater permit. DEEP approved the stormwater registrations for the early utility-scale solar projects in Connecticut without significant scrutiny, with the apparent expectation that the construction contractors and their stormwater professionals understood how to minimize erosion and sedimentation discharges during construction.  Unfortunately, there have been numerous incidents of significant stormwater damage and complaints from down-gradient property owners during and after the construction of solar facilities.  These problems have occurred either because the construction contractor, in an effort to meet contract deadlines, may have skipped steps such as failing to stage construction and clear only five acres at a time, or because the site engineers miscalculated the stormwater impacts from the extensive disturbance of the land’s natural condition.  In light of the repeated problems caused by erosion and sedimentation at solar construction sites, Connecticut has required more detailed site-specific documentation regarding stormwater flows and management systems, and has become more aggressive in its enforcement.   

In 2017 and 2018, DEEP issued several cease and desist orders temporarily halting the construction of solar projects until the projects revised their stormwater pollution control plans and installed improved erosion controls.  The Department also issued consent orders to some projects requiring remediation of impacted wetlands, watercourses and down-gradient properties, habitat restoration plans for some threatened species, and the posting of financial assurances of as much as $1 million. Two recent consent orders included civil penalties of between $200,000 and $575,000.  The Department also recently rejected a stormwater application for a 20 MW solar project, concluding that the submitted stormwater pollution control plan lacked sufficient detailed information necessary for the design of erosion and sediment controls and long term stormwater management measures post-construction to demonstrate that the project would adequately control stormwater impacts.

The lesson that should be learned from the Connecticut experience with constructing utility-scale solar projects is that developers need to devote sufficient resources to evaluate and design appropriate erosion and sedimentation controls earlier in the development process, and they need to hire qualified stormwater management consultants and pay careful attention to the proper implementation of stormwater controls, both during and after construction.  This means going beyond describing generic stormwater management controls in their applications for approval, and taking stormwater management seriously.  They need to understand that “A Hard Rains A-Gonna Fall” and cause damage to the environment if sufficient stormwater management controls are not correctly implemented.  If solar project sponsors are not careful, the public perception of solar projects will be negatively impacted by these stormwater-induced incidents, and support for these renewable energy projects will decline.

Add comment

  Country flag
  • Comment
  • Preview