Vaught Tributary of Lower Howards Creek Stormwater Model Extension and Study
Clark County, Winchester, KY
Palmer Engineering (Palmer) completed engineering analyses for the Vaught Tributary of Lower Howards Creek stormwater model in Winchester, Kentucky. With the goal of reducing peak flood stages in the watershed and improving water quality, four proposed alternatives were developed and evaluated against existing conditions at two different points of analysis along the stream. Palmer evaluated the effects of each proposed alternative against the existing flood stages and prepared a technical memorandum to describe criteria, assumptions, and guidelines referenced for the completed analyses.
The following scope was completed:
Extend and refine an existing hydrologic and hydraulic model, “Flood Study of Lower Howards Creek” (Palmer, 2008), to assess the potential effects of stormwater flooding in the Vaught Tributary
Develop alternative measures capable of reducing peak flood stages in the Vaught Tributary watershed and improving water quality
Implement these alternative measures in the hydrologic and hydraulic model to measure the efficacy of each
Compare existing conditions to the proposed conditions following completion of the proposed stormwater modeling
Identify the preferred alternative and prepare a planning-level cost estimate based on recent bid prices and engineering judgment
The preferred alternative involved the recommendation of a biofiltration basin on the property of the Robert D. Campbell Junior High School. A new outlet structure is proposed, and an existing drainage pipe along with the removal of approximately 7,000 cubic yards to provide additional storage volume. The preferred alternative was modeled to show approximately 6 inches of reduction in water surface elevation at the point of analysis for a 100-year, 24-hour storm event. The basin creation would allow for the settling of sediments and debris, pollutant removal through infiltration and uptake, and velocity dissipation reducing the potential for bank erosion downstream. The basin is proposed to be planted with native grasses and wildflowers. With the proposed project located on the property of the Clark County Board of Education, Palmer assisted in obtaining the Memorandum of Agreement for use of the land. Palmer presented the proposed project to the Clark County School Board to gain approval. The project will hopefully provide an outdoor learning space for students at the Junior High School.
After completion of the technical memorandum, Palmer presented the results to the City of Winchester Public Works Commission. Following recommendation of implementation, Palmer presented the preferred alternative to the City Council. Due to the previous preparation of the Lower Howards Creek Watershed Management Plan by Palmer, the project was awarded a 319(h) grant by the Kentucky Division of Water (KDOW). Palmer’s contract was negotiated to extend to include Phase 2 Design Services, which began in fall 2021, and construction is anticipated later in 2022.
