When selecting best management practices (BMPs) to protect streams during and following construction, riparian buffers are often considered the most effective option. These permanently vegetated areas alongside waterbodies can capture, infiltrate and control stormwater flow, filter contaminants, stabilize stream banks and otherwise help protect and restore waterbodies and the ecological functions they support. Recognizing the particular importance of riparian buffers located adjacent to exceptional value and high quality waters designated for special protection, the Pennsylvania Department of Environmental Protection (PADEP), like many other state environmental regulatory agencies, adopted regulations prohibiting earth disturbance activity within 150 feet of a special protection waterbody. The regulations further required a property developer to protect or establish a riparian forest buffer under certain circumstances where waters in the project’s watershed fail to attain their designated uses.
And then along came the Pennsylvania legislature. Faced with objections from homebuilders and other developers to restrictions on use of their properties, the legislature enacted Act 162 of 2014 to provide developers with additional options. Under Act 162, a developer who requires an NPDES stormwater construction permit may disturb land within 150 feet of a special protection waterbody if it implements BMPs “substantially equivalent” to a riparian buffer or a riparian forest buffer. If the earth disturbance would occur in a special protection watershed within 100 feet of a surface water, the developer must also offset any reduction of the total square footage of the buffer zone that would have been utilized as a BMP with a replacement buffer. The replacement buffer must be created in the same drainage area as the disturbed buffer and be as close as feasible to the area of disturbance at a ratio of one-to-one.
In response to the passage of Act 162, PADEP recently published interim final guidances on equivalency demonstration and offsetting. The equivalency demonstration guidance requires each developer disturbing earth within 150 feet of a special protection water to implement BMPs that reduce loadings of pollutants including total suspended solids, total phosphorous and nitrate. In addition, the developer must show that its BMPs are functionally equivalent to a riparian buffer or forested buffer by providing, among others, habit for wildlife and vegetation, flood attenuation, channel stability and support of aquatic food webs. Under the buffer offsetting guidance, a replacement buffer should be composed of native, diverse tree and shrub vegetation and preferably be installed at a location that receives runoff with characteristics similar to or more degraded than the runoff that the replaced buffer would have encountered.
While many regulatory regimes afford environmental agencies discretion to grant waivers and exceptions to buffer protection requirements, Pennsylvania has by statute granted developers the option of using substantially equivalent BMPs, supplemented where necessary by offsetting. PADEP has drafted guidances with stringent criteria for demonstrating equivalency and offsetting, but the guidances have yet to be finalized let alone judicially reviewed. Experience in administering Act 162 will reveal whether, under PADEP’s watchful eye, equivalency and offsetting can uniformly serve as effective substitutes for a prohibition on development near special protection waters. In the meanwhile, some healthy skepticism is in order.