Understanding Texas’ Coastal Wetlands – Their Values, Restoration, and Role in Sustainable Landscapes

Andrew Sipocz

Texas Parks and Wildlife Department

Topographic Map of Houston Area

Where is Houston?

Where is Galveston Bay?

Where is the high ground on this map?

What does this have to do with water pollution?

Liscum 2001

Large increase in runoff and peak discharge = greater need for channelization, bank erosion, loss of riparian vegetation and stream fauna

This worked well - TXDOT detention facility for SH 290

Background – Wetlands and Water Quality• Wetlands are able to transform or sequester some of our most

problematic water pollutants including inorganic nitrogen and phosphorous via bacterial respiration

• Wetlands are also able to sequester or denature metals and complex organic pollutants as PAHs via bacterial respiration

• Wetlands improve water clarity by trapping suspended sediment and flocculating colloidal sediment

• Wetlands remove infectious bacteria through UV exposure (they are shallow and have a high residence time) as well as viral and bacterial action

• Wetlands are increasingly being used to pre-treat polluted waters for drinking and as secondary, tertiary or even primary sewage treatment

• EX. Richland Creek Reservoir treats polluted Trinity River water before it enters the reservoir with large wetland impoundments

• EX. Everglades restoration is being accomplished by removal of agricultural phosphorous from runoff via large wetland impoundments.

Background – Wetlands and Water Quality

• Removal of pollutants can occur fairly quickly but requires aerobic and anaerobic periods and contact between water, soil and vegetation to promote facultative bacteria

• Removal efficiency increases with amount of contact, i.e. residence time of water

Mitsch and Gosselink Wetlands 2000

What role does science play in all of this?

Brays Bayou Wetland Creation Project