Harris County is more than halfway through drafting a countywide drainage master plan that will recommend neighborhood flood reduction projects in unincorporated areas, and the public comment map it is built around stays open through roughly the end of October.
The plan was presented at the September 22 meeting of the Harris County Community Flood Resilience Task Force by Steve Albert of the engineering firm DCCM, which serves as program manager on the project. ReduceFlooding.com, which covers Lake Houston area drainage, published the presentation and a detailed account of it Friday.
The effort matters locally because it is aimed squarely at the unincorporated county. Atascocita and Huffman sit in unincorporated Harris County and fall inside the study area. Kingwood does not, because Kingwood is inside Houston city limits, so drainage there remains the city’s responsibility rather than this plan’s.
What the Plan Covers
The Office of the County Engineer, under Dr. Milton Rahman, leads the work. It targets neighborhoods not already covered by previous or ongoing drainage projects, which Albert put at roughly two-thirds of the county’s approximately 1,800 square miles. A $12.5 million Texas General Land Office grant originally funded it.
Four firms each cover about a quarter of the county under DCCM: AECOM in the northwest, Michael Baker International in the south, HR Green in the central region and LAN in the east.
Albert drew a line between this work and the Harris County Flood Control District. Flood Control focuses on the bayous. County Engineering focuses on getting water to them, meaning smaller and more frequent storms, neighborhood drainage systems that cannot move water to a bayou, street flooding and the mobility problems that come with it. Albert said many communities flood well outside formal floodplain boundaries, which is the situation the plan is written for.
200 Scored Areas, and a Cluster in Atascocita
The project has identified 200 candidate areas, 50 in each of the four regions, each with a data sheet covering location, watershed, estimated cost and expected benefits. Of those, 60 will go through enhanced modeling to produce realistic cost estimates.
The public online viewer shows the four regions, the 200 areas, watershed boundaries, the county channel system, current FEMA floodplains, Flood Control detention basins, municipal utility districts and an address search. Bob Rehak of ReduceFlooding, reviewing the map, noted a large cluster of scored areas in Atascocita.
A caution on reading that map. Albert said the hexagons on it are not projects. They are roughly 200-acre scoring units used to rank flood potential, and the 200 shown are simply the highest-scoring units in the county. Actual projects are sized by local drainage area and may span several hexagons.
Residents can add comments directly to the map. Albert said a comment can be as simple as reporting backyard or street flooding in a small rain event, or naming an intersection that becomes impassable.
No Money Attached Yet
Albert said individual projects will generally run $1 million to $20 million and target more frequent one- to two-year storm events. Enhanced modeling is expected to finish in January 2027, with a final report issued before March 2027 for Commissioners Court approval.
There is no funding identified for any project on the list. Albert said a future bond program has been discussed. The stated purpose of the plan is to hand each precinct an engineering-based list to choose from, ranked on local priorities, the number of flooded homes a project would take out of harm’s way, and flooded roadway length.
