Harts Lake Loop Road South Horn Creek Culvert Replacement
Culverts
In this federally funded project, Herrera led preparation of hydraulic design reports, one for each of three culverts conveying unnamed tributaries of South Creek across State Route (SR) 7 and SR 161 in rural Pierce County. Herrera oversaw production of survey base maps to serve production of the design documents as well as the development of a two-dimensional hydraulic model for two of the three South Creek sites. The third, smallest culvert was simulated with a one-dimensional HEC-RAS hydraulic model. Herrera assessed geomorphic and habitat conditions at and near each of these road crossings, and a bankfull width determination was made in a reference reach associated with each stream/culvert that was agreed upon by the Washington Department of Fish & Wildlife (WDFW). The preliminary hydraulic design portion of the project work was completed on a fast track schedule. Construction of two of the three culvert replacements was completed in 2023. The third culvert is scheduled for construction in summer 2025