The ruling took effect in February 2010 and is being phased in over four years.  It is anticipated that compliance will positively impact the quality of water throughout the U.S because it tackles one of the leading causes of water quality problems nationwide, soil and sediment runoff from construction.

This EPA rule requires construction site owners and operators that disturb one or more acres to use best management practices (BMPs) to ensure that soil disturbed during construction activity does not pollute nearby water bodies. In addition, owners and operators of sites that impact 10 or more acres of land at one time will be required to monitor discharges and ensure they comply with specific limits on discharges to minimize the impact on nearby water bodies.

This monitoring requirement is a different approach for the EPA because it incorporates a technology “floor” which sets out a numeric standard on the clarity of the water discharged from the developer’s site.  The EPA’s final standard is 280 NTUs.  This is less stringent than what was originally proposed, a limit of 13 NTU’s, a very clean discharge, but still translates into construction cost increases.

The criterion for storm water displacement is based on the amount of rain received on a site over a 2 year period.  The volume of water is calculated and that becomes the benchmark. For example construction of a building with parking lots could be projected at 250,000 gallons of diverted water.  Rather than allowing this water to run off, it needs to be held somehow on the site and allowed to re-integrate with the soil.

Examples of available options for controlling this run off might include green roofing, a popular but expensive method.  A less expensive alternative is developing a “recharge area” defined as a space typically stone filled, that resides underground on the site.  Where a green roof could be assessed at $192 a cubic foot, a recharge area of crushed stone might be estimated at $7 a cubic foot. In addition, both alternatives might be needed, as often one tactic doesn’t provide enough capacity.

In addition to planning for water displacement, if there is a stream or waterway on a site the buffer area where construction is prohibited has expanded from 50 ft to 150 ft.  The objective is to ensure that the construction doesn’t contribute to the degradation of that waterway; that the high quality of the water is protected.  This means there is less area that can be developed and in some instances sites that can’t be developed at all.  It is another good reason to bring in the experts early in the buying and building process.

Runoff and soil erosion are managed during the actual construction process by using techniques outlined by the EPA called Best Management Practices (BMPs) to reduce construction-related pollution.  BMPs result in such activities as minimizing land clearing, building proper site entrances, stabilizing steep slopes, installing sediment traps and perimeter controls like sediment basins.  Other BMPs involve good housekeeping measures, like picking up site debris, and cleaning vehicles in designated washing areas. Again, using a single control mea­sure, such as a silt fence, is rarely adequate. To be most effective, several of these BMPs need to be used in combination.

In addition to adopting these BMPs, under the Clean Water Act, certain construction sites must obtain a National Pollutant Discharge Elimination System (NPDES) permit. This permit enables operators of these sites to implement steps to prevent sediment and other pollutants from washing off into nearby waterways.  The permit, which requires a plan document, in the past was available for 5 years and could be extended.  Currently however, only 2-year non-renewable permits are available.

The two-year permit is an indication that the guidelines and accompanying laws are in great flux.  There is a lot of uncertainty surrounding the regulations and what will happen in the future; a fact that is born out by the case involving Crum Creek.  The case is on appeal before the Pennsylvania Commonwealth Court and raises issues surrounding the development activities in the state’s special protection watersheds.

In Crum Creek Neighbors v. DEP, the Pennsylvania Environmental Hearing Board (EHB) remanded an erosion and sedimentation control (E&S) permit, an NPDES, issued by the Department of Environmental Protection (DEP).  It was remanded because the court determined that further analysis under Pennsylvania’s “antidegradation” regulations governing discharges to special protection streams, was needed.  Special protection streams are those streams with designations of “high quality” or “exceptional value”.

The EHB held that DEP should have further analyzed whether a proposed construction project would result in discharges into a special protection stream even though the permittee (Pulte Homes of PA) designed an erosion and sedimentation control plan and “post-construction stormwater management plan” consistent with best management practices (BMPs)  The EHB also ruled that DEP was compelled to evaluate whether the proposed construction activities associated with the development would alter the groundwater flow feeding the nearby special protection stream and thereby ‘degrade’ that stream.

This ruling leaves architects and builders in a precarious position as the EHB’s decision suggests that a having a DEP permit may not be ensure the EPA’s approval, even if the applicant submits plans that comply with regulatory requirements and implements BMPs to minimize discharges into a special protection waterway.

In addition, the EHB’s interpretation of antidegradation rules presents significant challenges to both the DEP and construction planners because it opened up consideration of the indirect impacts on water quantity and quality, such as groundwater flow disruption.  So even if all the approvals are obtained and the rules are followed, developers can still get in trouble and like any new rules, these will take a while to shake down and get used to.