The Greens Bayou watershed in north Harris County covers 212 sq miles, parts of Houston and Humble, Texas, and includes primary tributaries: Greens Bayou, Halls Bayou, Garners Bayou and Reinhardt Bayou. Storms influence the lower 10 miles of the watershed, which is highly developed and densely populated. Significant damage to the homes and businesses located within the floodplain have occurred more than a dozen times during the past 20 years.
To combat repetitive flooding and reduce flood damage, Harris County Flood Control District (HCFCD) employed Challenger Services Inc., a full service excavation and heavy equipment company based in Texas, to excavate and construct the $16 million dollar Lauder Stormwater Detention Basin.
Harris County Flood Control District purchased more than 90 acres, as well as parts of Castlewood, a major subdivision, to help with the basin excavation and expansion effort. The Lauder Stormwater Basin Project includes excavating the storm water detention on the original Lauder Site, Lauder Road, Castlewood and the Greens Bayou tributary.
The Lauder Detention Basin is designed to improve storm water quality while protecting a 200-ft wide wooded area along the Greens Bayou tributary. Construction of the Lauder Detention Basin, a wet-bottom basin, will store overflow and slowly release storm water back into the bayou during future storms. The Lauder Stormwater Detention Basin will hold at least 1,200 acre ft or more than 391 million gal of surplus storm water.
An important source of environmental and storm water protection, Construction EcoServices provided Challenger Services Inc. with 16 FODS (Foreign Object Debris System) Trackout Control Mats, placed at the entrances to the excavation site. FODS Trackout Control System eliminates fugitive debris from exiting a worksite and entering storm water runoff. The mats are designed to be durable and reusable with easy installation, cleaning and transport.
During the intermediate excavation at Lauder Road, Harris County Flood Control District conducted best management practice (BMP), product approval testing on the mats over 178 active excavation days with 29,745 fully loaded trucks leaving the site. HCFCD Construction Division developed criteria to measure the performance of the mats. Data was collected regarding durability, maintenance, and permit compliance to determine if FODS met or exceeded the performance of traditional, three-by-five rock Stabilized Construction Access (SCA) HCFCD Specification 02365. Maintaining clean local roadways was also an element of required good housekeeping for compliance with the Construction General Permit.
HCFCD analyzed data and determined that “FODS provided equal or greater performance than SCA.” Use of the mats decreased roadway cleaning by 59%. FODS required more frequent cleaning; however, the cleaning effort was less time consuming and resulted in a cleaner roadway.
Harris County Flood Control District has officially added FODS as an approved best management practice and stated, “it is recommended that a special specification be created for FODS as an alternative to SCA.”
Use of FODS improved Challenger Services Inc. compliance with the Construction General Permit and reduced liability by preventing dirt tracked onto Lauder Road and successfully mitigated construction site debris from entering storm water runoff.