Department of Energy Mitigation Bank
Westminster, CO

In 1996 Aquatic and Wetland Company (AWC) had the opportunity to design and construct one of the first wetland mitigation banks in the State of Colorado.  Mitigation banking is a relatively new environmental management technique which allows a project sponsor to create wetland habitat in advance of anticipated future wetland impacts.  Total mitigation is tracked on a balance sheet using a credit and debit method; created wetland acreage is recorded as a credit and impacted wetland acreage as a debit.  The purpose of a mitigation banking system is to increase efficiency and reduce the cost of mitigation.  This system also provides a means of consolidating compensatory mitigation for impacts to small, isolated, fragmented wetlands into larger parcels that provide enhanced wetland functions and values.

To compensate for potential future impacts to wetlands during the Rocky Flats Environmental Technology Site clean up, the Department of Energy DOE in conjunction with the City of Westminster retained AWC to create 12 acres of wetland in proximity to Standley Lake. AWC was a key participant in coordinating with the DOE and other regulatory agencies on developing the physical and institutional requirements associated with the bank development.  Final site selection and concept design was coordinated with the City.

AWC was responsible for the final design, construction and production of plant materials for the wetland creation site.  Basic design elements include an open channel water distribution system with sediment control designed to mimic a “leaky ditch system.”  Four different vegetative zones were planted at the site, including a palustrine emergent meadow zone, a cottonwood/shrub zone, a transitional wet meadow zone and a cottonwood/leadplant zone.  A total of 63,000 plants of 12 different varieties were planted.  All of the plant materials were contract grown at the AWC nursery facilities from site collected seeds and cuttings.  Follow-up monitoring and maintenance will continue on the site for 5 years to ensure the healthy establishment of wetland functions.

This project is a good example of how mitigation banking works well to account for impacts to small fragmented wetlands and how to compensate for them in larger parcels which will provide a higher level of wetland functions and values.