Client: Durham County Open Space
Location: Durham, NC
Durham County has numerous trails occupying low-lying floodplain areas. While very popular, the location of these trails presents challenges due to frequent flooding which leaves the tread surface mucky and potentially with standing water for extended durations where heavy foot traffic has created ruts. In addition, there was a creek crossing across an ephemeral oxbow that was orginally built with multiple 18″ culverts and topped with loose #57 stone. Due to the culverts being undersized, they would clog fairly quickly and cause flood waters to breach over the crossing and wipe out the trail.
Durham County contacted us about solving both of these problems. First, we removed the old culverts and installed a custom 10ft x 10ft aluminum box culvert that allows for substantially more water flow, reduces the likelyhood of clogging, and is easier to maintain in the event of storm debris buildup. Next, we rehabilitated and armored the floodplain trail to prevent further erosion. This stone is up to 3″ in diameter and nests together to form a faily smooth surface due to the angular sides. In addition, due to the moderate size of the stone, it is heavy enough to resist lifting and being displaced by water flow unlike finer #57, #67, #78, ABC, or rock screenings often used on trails in less flood prone areas.