Environmental Services Expedite Trail Restoration
The Cedar Valley Nature Trail traverses nearly 52 miles from Evansdale to Hiawatha, crossing the Cedar River at multiple points. Both the Evansdale Trail Bridge and the trail bridge in McFarlane Park, just east of La Porte City were severely damaged in the 2008 flood event and closed due to safety concerns that necessitated complete reconstruction. When it came to the reconstruction of the bridges and the flood-damaged sections of the trail, Black Hawk County leaders recognized the trail’s path through the floodplain of the Cedar River, forested areas, wetlands, and rolling farmlands would require a multitude of environmental services. The environmental experts with Snyder & Associates were brought on board to guide this challenging project through the labyrinth of wetland mitigation permitting.McFarlane & Evansdale Bridges Key to Trail Restoration
The McFarlane Trail Bridge, originally built as part of the Waterloo, Cedar Falls, and Northern Railroad (WCF&N), featured dramatic closed-spandrel arches, while its proposed replacement boasts a modern structure that stretches 728-feet long. Similarly, the proposed Evansdale structure stands six feet taller than its predecessor and spans 576-feet over the Cedar River, providing a 12-foot wide path for trail users.
McFarlane Bridge before flooding and reconstruction.
Maintaining Wetland Habitat & Biodiversity through Replacement
Before the type of mitigation is determined, the process requires that actions be taken during the planning phase to minimize the impacts of construction. If impacts are determined to be permanent, mitigation bank credits can be purchased to offset the effects. If credits are not available, an alternative site can be located to create or enhance a wetlands area. Wetlands that are temporarily impacted during construction may be restored to preconstruction conditions. For the Evansdale and McFarlane Bridge projects, wetland credits were not available. It was decided that creating wetlands off-site was the best option. This decision, however, introduced the challenge of finding available land. Our team assisted in forming a partnership between Black Hawk County and Tama County to find a suitable land replacement for the wetland areas lost through the projects. With this union established, approximately two acres of land was allotted for wetland creation at Hickory Hills Park located southwest of La Porte City. At the project sites, the impacted wetlands were classified as both emergent and forested wetlands. These same varieties were replicated in Hickory Hills Park at higher ratios, otherwise known as in-kind mitigation.
Wetland mitigation site at Hickory Hills Park was used to compensate for wetland loss during trail construction.

