Article of Interest

Stormwater Management Challenges

Changing Weather Patterns and Evolving Regulations Necessitate Stormwater Management Strategies

The recent weather patterns across the Northeast have been erratic with more extreme variations. The old adage “If you don’t like the weather, then wait a minute” has never been truer. Few of us will ever forget the devastating storms that took place across the region in May 2006. The rains produced floods in record proportions and caused significant property damage and economic hardship.

The changing weather patterns coupled with expanding development are significantly increasing stormwater quantities, and stream and river flow. In many cases, existing stormwater infrastructure was designed to accommodate less severe conditions, and lacks adequate capacity to accommodate the new higher flow conditions. As a result, flooding problems are becoming more common. Looking ahead, many communities will need to develop a hydraulic capacity analysis of the critical stormwater elements to identify undersized elements and to develop a prioritized upgrade plan to prevent future flooding and property damage.

Stormwater management is not only about flood control, it’s also about water quality. Wright-Pierce has assisted numerous communities with the implementation and required reporting of the federally mandated Stormwater Phase II program for regulated municipal separate storm sewer systems (MS4s). The intent of National Pollution Discharge Elimination System (NPDES) stormwater permitting is to preserve and protect water quality and improve our natural resources from polluted stormwater runoff. Each regulated MS4 aims at doing this through the development of a stormwater program management plan (SWPMP) that details the required six minimum control measures and associated measurable goals to be implemented over a five-year period.

This year is the end of the first five-year permit cycle of the General Permit, and it has been a learning experience for everyone involved. Regulatory agencies will be assessing how effective communities have been at implementing their Stormwater Phase II programs, the challenges they have faced, and how they will accomplish any outstanding measurable goals in the next permit cycle.

The next permit cycle will require even more of communities, particularly as it relates to mapping of drainage systems and addressing impaired  receiving waters. Going forward, it is important to continue to integrate stormwater management, including Stormwater Phase II requirements, as part of an overall comprehensive approach to municipal operations.