BPA: Demonstration Project would stabilize bayou in more natural state

A controversy has arisen concerning a permit application to the U.S. Army Corps of Engineers by the Harris County Flood Control District related to a stream/bank restoration and erosion control project on Buffalo Bayou known as the Memorial Park Demonstration Project (Project). The Bayou Preservation Association (BPA) supports the Project because it will address an active and increasingly growing erosion problem on Buffalo Bayou that is destructive to riparian flora, fauna, native habitat and it’s banks.

BPA is a local non-profit corporation with a mission to “to protect and restore the richness and diversity of [Houston area] waterways”. In BPA’s view, the Project is critical in helping to stabilize Buffalo Bayou in a more natural and sustainable state using Natural Channel Design. Some public controversy arises from a mistaken impression that Buffalo Bayou in the vicinity of Memorial Park and the River Oaks Country Club is in a “natural” condition. It is certainly true that there are trees, vegetation and wildlife in the area, but the channel and banks of the bayou are suffering from severe erosion caused by stressed conditions related to it’s modified or reduced floodplain.

BPA understands and respects the concerns of those who fear any project near Memorial Park. It is wrong, however, to view stopping the Project as “preservation”. The occupation of these riparian habitats and beyond has created irreversible conditions that the bayou is attempting to adjust to but without the space it requires to create stable slopes. Stormwater that once took days to reach the bayou channel and ramped up and down slowly now fills the channel from bank to bank in a matter of hours producing flash-flood erosion generating conditions. Moreover, artificial flow rates of stormwater released from the Addicks and Barker Reservoirs allow for prolonged saturation and bank failure.

The Project is worthy of support because it follows NCD design principles. NCD is a holistic approach to stream restoration and stabilization pioneered by Dr. Dave Rosgen, a Colorado hydrologist. It is a science-based method of stream restoration that uses river science (“fluvial geomorphology”) to restore stream banks and bayou channels to stable configurations that river scientists predict the stream would achieve over long time frames.

Fear of construction is understandable. Habitat, trees and vegetation will be disrupted and some trees will be removed. The majority of the potentially affected trees are on a single tract of private land that has already suffered tremendous losses of land and forest, and will likely lose the remainder if nothing is done that supports natural bank stabilization. The Project includes a plan to replace the collected topsoil after construction. The Project will use natural woody material for structural support. Revegetation methods with native soils and plants on stabilized banks will restore habitat quicker than allowing the banks to move about until such time that it acquires additional land if available and then seeks it’s own point of stability.

It is important to understand that of the 972 trees surveyed in the Project reach, 73 are dead and many others are in a declining state. Only 180 trees are in the impact zone. Many of the surveyed trees are invasive species such as Chinese Tallow, Camphor, Chinaberry, Arizona Ash, Ligustrum and Red Mulberry that are introduced species that also encourage native habitat loss through their short life spans, aggressive root systems and shading of the native trees that could be providing food, long-term bank stability and habitat.

BPA encourages everyone to support the Memorial Park Demonstration Project and to get involved in bayou preservation. After all, we are the Bayou City.

Robert Rayburn is president of the Bayou Preservation Association. He can be reached at bpa@bayoupreservation.org.