The Floodgates Open: What pressures will 3.5 million people exert on our floodplains?


Jan. 24, 2007


Taebel, J

Journal Title

Journal ISSN

Volume Title


Galveston Bay Estuary Program


This presentation will provide an overview of where future growth is projected and its impacts on flood plains and other natural systems in the Galveston Bay watersheds. Alternative growth scenarios and policy options for reducing or mitigating the impacts of this growth will also be explored. The Houston-Galveston Area Council (H-GAC) forecasts regional growth of more than 3.5 million people by the year 2035. Using a model that simulates urban development dynamics, H-GAC projects significant residential development within the region's flood plains that will house 1.3 million of these new residents. The magnitude of expected growth will entail a significant conversion of natural drainage and storm water detention systems into manmade systems. It also has the potential to alter or consume important habitat. Additionally, new development throughout the Galveston Bay watershed is forecasted to add 300 square miles of impervious surface. However, H-GAC's forecast is predicated on a "business as usual" assumption with respect to urban growth policies (or lack thereof). An alternative scenario has also been prepared by H-GAC, where all new growth in the flood plain is restricted. Results of this scenario will be reviewed, along with a discussion of the types of policies that would be necessary to effectively prevent future flood plain development. The potential of other methods of mitigating the impacts of future development will also be explored, including cluster subdivisions, low impact development and micro detention.




development, habitat loss, impervious surface, population growth