Navigating Wetlands and Their Impact on Utility-Scale Solar Design

In an era where utility-scale solar development is rapidly expanding across the United States, understanding and protecting wetlands has become increasingly critical for project success. As wetlands now cover less than 6% of the lower 48 states – half of what existed in the 1780s according to U.S. Fish and Wildlife Service data – developers must carefully consider these ecosystems during site selection and design. While wetlands can present complex challenges for solar projects, with numerous different regulatory agencies potentially involved in a single location, careful planning and understanding of wetland classifications can help developers navigate these sensitive ecosystems. 

Let’s tune into this excerpt from John Selby from the Utility-Scale Solar Design Applications course to learn more about wetlands considerations in large-scale solar development. 

Transcript below.

Let’s start this lesson by looking at those three orange surveys in more detail. First up, we need to consider any flood zones or wetlands to determine if there are regions of the site which will need to be excluded from the available area for modules and equipment. 

Flood zones can generally be determined by national maps, and if present, they may exclude areas or require that electrical equipment be elevated to prevent it from being submerged. 

Wetlands, if present, may require a special survey by a biologist in addition to your topographic and ALTA surveys. However, if you see wetland identified on a survey, don’t necessarily jump to the conclusion that those areas are total no-go’s.  

Wetlands have two major types: non-jurisdictional and jurisdictional. 

Non-jurisdictional wetlands are typically smaller and less regulated. You’ll need to check with your local AHJ and state agency to determine what modifications are acceptable for these areas. Not to say that they shouldn’t be a consideration for the civil design, but the developer may be able to fill them in, place solar posts within them, trench through them, etc. 

Jurisdictional wetlands are regulated by an agency, which could be the state or could be the U.S. Army Corps of Engineers, which actually gets involved in wetlands of a surprisingly small size. These areas are more heavily regulated and require projects to adapt array footprints or limit clearing of vegetation. 

Wetlands, especially ones deemed to be significant by the Army Corps or the state, should be carefully dealt with during the development and design process.  In addition to hefty fines for non-compliance, we also want to preserve local ecosystems while doing our work.  

Just to give you a sense of how complex the wetland issue can be, let’s look at an example from Illinois. There are five different agencies that might be involved in regulating a wetland area. So do your homework and make sure you’re in compliance.  

Like many aspects of the design that we’ll look at in this course, we’re in a golden age of information and mapping tools for PV site design. If you’re doing project development and you want to check if your project area may border or encompass a jurisdictional wetland, there are resources available.

This one is from New York State, and right now I’m showing several types of wetlands in the National Wetland Inventory.  As you can see, there’s several categories of wetlands that sometimes overlap one another. Each with different levels of disturbance or modification that may or may not be permitted.