Hardin County Hurricane Ike/Dolly Recovery Projects
KSA was hired by the General Land Office to complete several projects in Hardin County, Texas to address flooding that occurred during Hurricane Ike. Much of the southern portion of the county is approximately 20 feet above sea level. Hardin County is located sufficiently inland to avoid the worst wind effects of gulf storms but received extensive rain during the storm event. Under the Disaster Recovery Program, Hardin County has funded two significant flood control projects.
The Silsbee Detention basin was designed adjacent to Mill Creek to protect Quail Hollow Subdivision. Quail Hollow is a 90-acre subdivision located outside the City of Silsbee city limits. The area is not identified as a flood hazard on FEMA mapping but experienced ponding around building structures with rain events with as low as two year reoccurrence intervals. Hurricane Ike inundated homes and structures. KSA coordinated with the county to design a diversion channel to capture the out of bank flow volume in Mill Creek and direct the flow to a storm water detention pond. The detention basin discharges back into Mill Creek south of Quail Hollow.
Hardin County’s second project involved mitigating flooding in the Pinewood and Countrywood communities. These communities have experienced significant periodic flooding and flooded during the 2008 hurricane. KSA completed a flood study for this area in 1994 and updated the information in 2006. The need for improvements in this area were well known. However, funding was unavailable. The Pinewood and Countrywood communities combined represent approximately 1500 acres of residential development centered about Coon Marsh Gulley. Approximately 60% of the community is located within a Zone A flood hazard. KSA completed a detailed topographical survey of Coon Marsh Gully and the adjoining residential area. Significant challenges were present with the improvements. Most of the land in the area was already developed and the current floodplain was extensive. The budget for the improvements also precluded construction of detention reservoirs or storm water pumping. Significant environmental issues existed including potential threatened and endangered species. The project also terminated at the Big Thicket National Preserve.
Will all these obstacles KSA developed several options. The recommended option included removing brush and debris from a mile long portion of an existing diversion channel, concrete lining 1,500 linear feet of diversion channel through the most developed portion of Pinewood Estates, and construction of 1.25-mile grass lined diversion channel around portions of Countrywood Estates. Flow restrictions were found at two bridges on Coon Marsh Gulley. The Pinewood Boulevard bridge was concrete lined to increase conveyance and the Bonura Road crossing was rebuilt with larger box culverts.