STORMWATER MANAGEMENT
CFS provides long term solutions for stormwater to meet future needs and projected regulation requirements. CFS performs watershed delineation, hydrologic modeling, hydraulic modeling, floodplain mapping, and storm drain modeling. We utilize various methodologies, including HEC-1, HEC-RAS, HMS, TR-20, TR-55 and Rational. CFS analyzes open-channel drainage systems and existing natural streams for FEMA flood studies and regularly prepares and files documents of map revision.
CFS has designed stormwater management projects with construction costs ranging from $10,000 to $2 million for state, county, municipal and private projects in Kansas and Missouri. CFS offers a range of stormwater drainage design and evaluation services for enclosed storm sewer systems, open-channels and bridge hydraulics. The firm has designed projects for upgrading and improving existing drainage systems in fully developed urban areas, and has designed regional stormwater detention basins to help alleviate flooding in downstream areas with restricted capacities. CFS has prepared intricate erosion control plans for street and large land disturbance projects to comply with the environmental NPDES requirements. The company has also worked with FEMA and the Corps for open-channel flow evaluation and applications for no-rise certificates for properties in floodplains and overbank areas.
PROJECTS
4th & Walnut Storm Sewer
Wellsville, Kansas
The project included grading and concrete paving for the ditch within utility easement between 3rd Street and 4th Street. The stormwater enters an enclosed storm sewer system north of 4th Street and is routed around the property located at the Southwest corner of 4th and Walnut. The storm system crosses Walnut Street before discharging into an open ditch section to the Southwest. There were two roadway crossings which required removal of the existing cross road culverts and pavement replacement. Traffic control plans were developed to detour around this work. The road closures at these locations lasted only one week and access to local properties was maintained through construction. Approximately 800 lineal feet of storm sewer pipe ranging in size from 12” to 60” in diameter was designed by CFS with associated inlets and junction boxes. The project included 400 lineal feet of open channel storm sewer improvements, demolition and removal of the existing storm drainage facilities, the acquisition of easements, the removal and replacement of pavements and sidewalks, the relocation of utilities, grading, erosion control, traffic control, and signage.
CFS was responsible for project leadership, communications with property owners, surveying, construction documents, permitting with KDHE, KDWPT, SHPO, CORPS, bidding and Construction Services. CFS provided utility coordination and relocation, environmental and cultural permitting, easement acquisition, and construction documents. The project was designed using APWA specifications and did not require extensive technical specifications.
Turkey Creek Flood Rise Analysis
Lenexa, Kansas
The Haren-Laughlin Construction Company proposed to place some available fill material on the overbank area on the western side of Turkey Creek, at the company's headquarters located at 8034 and 8035 Nieman Road in Lenexa, Kansas.Their desire was to expand their current operations with 9 new parking spaces using pervious concrete, a new patio, and building addition. Because of the close location to Turkey Creek, CFS completed a flood plain study and CLOMR application.
As a result of the study, CFS determined that the proposed improvements would not cause the 100-year water surface elevation to rise within the floodway area. CFS compared results from the HEC-RAS models for the Turkey Creek for the existing conditions and for the proposed fill placement at River Station 6.306.
CFS provided survey, hydrologic modeling and civil engineering design.
Christian County Stormwater
Study and Masterplan
Christian County, Missouri
Christian County, Missouri located between Springfield and Branson has experienced an increase in population beginning in the early 2000’s. This increase in population brought with it an exponential increase in development and impervious land coverage. This increase in impervious area was not accounted for when the aging stormwater infrastructure was designed and put into place. The stormwater infrastructure is woefully inadequate and the entire county is experiencing significant flooding.
The Christian County Commission made the decision to use American Rescue Plan Act (ARPA) funding to solve many of the county’s recurring stormwater flooding issues. The CFS Team is one of four consultant teams selected to develop a detailed stormwater master plan for a watershed in the county. CFS is responsible for the Swan Creek watershed which has a drainage area, within the county, of approximately 76,000 acres.
Using H&H modeling in conjunction with public input CFS has identified priority areas which need to be studied. The goal of this work is to identify the most common flooding locations in order to protect and improve the overall level of water quality through better runoff management. CFS will create a prioritized list of projects that can be constructed with ARPA funds. Once the projects are identified design and construction plans can be developed.
