DESTRUCTION BY DESIGN: The U.S. Army Corps of Engineers’ Continuing  Assault on America’s Environment

CALAMITOUS CHANNELIZATION: The Case of Clear Creek Texas (Return to Contents)

In a misguided effort at flood control, the Army Corps of Engineers intends to spend over $100 million dollars to channelize Clear Creek in suburban Houston, Texas to protect a handful of residents from a 10-year flood event. The project will devastate the only remaining, largely intact freshwater bayou system in the greater Houston area, but will do little to address the flooding problems, and may ultimately increase flood damages. A less expensive and wiser alternative would be to simply buy the flood prone lands and move at-risk property owners out of the floodplain, estimated to be half the cost of the proposed channelization project. This nonstructural approach would preserve the important wetland resources of the area, provide protection from a 100-year flood event, and protect the water quality of Clear Creek, and the adjoining Clear Lake and Galveston Bay.

Clear Creek is a tidally influenced bayou that meanders for 40 miles from its upstream origin in Fort Bend County, Texas, to its lower reaches in Harris and Galveston Counties, south of Houston. The Clear Creek watershed, which includes Armand Bayou, drains approximately 260 square miles. The Creek officially terminates as it enters Clear Lake, which eventually empties into Galveston Bay.

The bayous, tributaries and floodplains of Clear Creek are vegetated with green ash and towering oaks that provide lush habitat for terrestrial and aquatic species, including wood ducks, spotted sandpipers, ospreys and beautiful roseate spoonbills. The Creek supports large stands of mature, almost unbroken bottomland hardwood forest dominated by live oaks and water oaks. The tidal hydrology and sediment regime associated with the Creek is important for maintaining the diversity and health of a variety of wildlife. Great numbers of mammals, birds, reptiles and amphibians rely on the ecosystem for food, water, shelter, breeding and nesting. The shallow vegetated fresh water habitat, protected from the open bays below Houston, provides valuable breeding and nursery grounds for a variety of fish species. Water movement patterns in the Creek create a variety of conditions, such as riffles and pools, that are critical in supporting habitat for more than 50 fish and three shrimp species—many of which are recreationally and commercially important. The Creek's wetlands also serve as a sponge for runoff from urbanized areas bordering Clear Creek and Clear Lake, naturally cleansing the water before it empties into Galveston Bay or seeps into local groundwater supplies. Rapid urbanization of developable uplands adjacent to the Creek make its bottomland hardwood forest especially important as a last refuge for numerous animal species that once occupied vast ranges of the coastal plain.

The Corps is proceeding with a project that will turn the 21 mile stretch of creek running from the western end of Clear Lake to Pearland, into a 15 mile, 330-foot wide straight channel, cleared of all trees, wetland vegetation, or other potential obstructions. The intent of the project is to deepen, widen, and straighten the creek to move high volumes of water swiftly away from flood prone areas. The project is designed to handle a 10-year storm event. Increased flow in this channel would inevitably increase water levels downstream and in Clear Lake. To address the increased water levels, the project called for construction of an artificial outlet from Clear Lake to Galveston Bay. The outlet was completed in 1996. Construction of this Corps project is estimated at $129 million.

Funding for the plan to channelize Clear Creek first received Congressional authorization in 1968, but remained virtually dormant until rains associated with Hurricane Claudette in 1979 deluged the area. The project was developed in response to complaints from Galveston County and the Harris County Flood Control District about flooding in the areas of Friendswood and Pearland.

In 1996, in response to opposition voiced by local citizens groups, communities and government agencies, the Harris County Flood Control District entered into a six-month restudy of the project. In December of 1997, the District issued an alternative to the Corps' project, referred to as the HCFCD Plan. The HCFCD Plan is also a structural channelization project, although the depth and width of the channel are reduced. The costs of the HCFCD Plan are estimated at $122 million. The District presented the plan to the Corps for review. The Corps has now entered into a restudy of the Clear Creek project in light of the HCFCD Plan and other issues.

Both structural channelization alternatives would eliminate valuable oxbows, wetlands and marsh areas, although the HCFCD Plan reduces the proposed destruction of forest and wetlands associated with the Corps' project design. In-stream snags that are prime fish habitat will be removed. Channelization will lower the stream, dewater floodplains and oxbows by lowering the water table, and adversely affect wetland vegetation. This, in turn, will negatively impact the fish and shellfish populations dependent upon the Creek. Reduced filtration of increased runoff threatens to degrade water quality of the Creek, as well as Clear Lake and Galveston Bay into which it runs.

Channelization will shorten and straighten the Creek, resulting in faster currents and higher stream flows during storm events. The Corps has projected that runoff would raise lake levels at Clear Lake by 2.5 to 3 feet during a 100-year flood event.

Channelization will also result in faster transport of contaminants into Clear Lake and, ultimately, Galveston Bay. Present threats to shellfish populations in Galveston Bay posed by water quality degradation in Clear Creek and its other tributaries will be increased. Moreover, channelization will disturb sediments of the Creek and its tributaries. The Brio Refinery, a Superfund toxic waste site located along a tributary to Clear Creek known as Mud Gully, has the potential for making this problematic. Toxic chemicals have leaked into Mud Gully and adjacent lands, contaminating the Creek's sediments. Contaminant levels in this area are significant. Disturbance of these sediments could release and mobilize the contaminants, threatening human health and the environment.

Furthermore, the project will remove important hardwood forest habitats and fragment increasingly rare riparian habitat. Loss of these habitats will likely mean the extirpation of several species of wildlife, including terrestrial predators such as the bobcat and gray fox and will adversely impact other wildlife. Channelization will also narrow the floodplain, making more land available for development, thus further reducing and fragmenting available riparian habitat.

A recent analysis of the Corps' design of the project concluded it would actually raise flood levels around Clear Creek under certain tidal conditions. As discussed previously, the channelization of Clear Creek would significantly increase flows into Clear Lake during storm events. To compensate for this, an outlet to Galveston Bay was constructed by the Corps to release this excess water. In considering its design of the outlet, the Corps assumed that high tides and rainfall/runoff events were not likely to occur at the same time. Subsequent analyses found this assumption to be invalid. In fact, as presently designed, if the water level in the lake is lower than the water level in the Bay, as occurs during certain tidal conditions, the outlet cannot release the water as intended and flood levels in the area around Clear Lake will rise.

The Corps also assumed that all future development in the watershed would occur without any significant increase in runoff to the watershed. This assumption is surprising as the project was economically justified primarily on the basis that it would open flood prone lands to development, and development generally increases runoff. Nonetheless, the assumption has proved incorrect. The Harris County Flood Control District found that future development of the watershed would result in a significant increase in the runoff entering the lake. Existing runoff rates could only be maintained if all future development was required to have on-site detention. Since the outlet constructed by the Corps was not sufficiently large to handle increases in runoff associated with development, they concluded that the outlet clearly could not accommodate additional increases in runoff.

In short, the Corps has spent 30 years and $40 million on the design and construction of a project that will not effectively reduce the flooding problems it was created to address. The Corps is in the process of a "restudy" of the project. It can only be hoped that at the conclusion of this process the Corps will adopt a design that effectively addresses the problems faced by the residents of Clear Creek and Clear Lake.

The approaches adopted by both the Corps and the Harris County Flood Control District are structural approaches to the periodic flooding in the Clear Creek floodplain. These schemes are geared to open additional floodprone lands to development and thus leave homeowners in harms way. Such structural approaches continue a federal policy that has proved costly and ineffective.

National policy requires examination, consideration, and use of nonstructural flood control measures wherever appropriate. This policy was set forth in detail in Guidance issued in February 1997 by the Office of Management and Budget and the Council on Environmental Quality. This Guidance mandates consideration of long-term alternatives to structural flood protection efforts. Among other things, the Guidance requires each federal agency to ensure a "cost-effective approach to flood damage mitigation and floodplain management and the protection of important environmental and natural resource values that are inherent to the floodplain and adjacent lands."

Nonstructural alternatives do not physically alter streams or creeks, generally provide more comprehensive solutions to flooding, and have proven more sustainable and cost-effective in the long-term. In the case of Clear Creek there exists a viable, less costly nonstructural alternative—the Buyout Plan. Under this Plan the Corps would acquire 400 homes in the Friendswood area, representing all homes in the 100-year floodplain within the limits of the Corps project area. The Buyout Plan is acknowledged to have the least environmental impacts and would cost only $60 million, much less than the structural alternative. The only project purpose not served by the Buyout Plan is drainage of the floodplain in the upper reaches of Clear Creek to provide opportunities for future development—a purpose whose propriety has been questioned.

The Buyout Plan is clearly consistent with current National Guidelines, as well as Congressionally mandated and Administration initiated reviews of floodplain management policies ordered after the disastrous 1993 Mississippi River floods. Preservation of bottomland hardwood forests, wetlands, and natural hydrographs; the movement of at-risk populations and structures from floodprone areas; and an emphasis on protection of natural floodplain habitats are the preferred methods of addressing continual flooding.

Flooding problems in the Clear Creek watershed result from development of the Creek's floodplains. Since 1968, the Clear Creek floodplain has increasingly been encroached upon by housing developments, new roads, shopping centers, large parking lots, acres of new concrete, and hundreds of hard urban grassy lawns. As of 1997, about 10 percent of the floodplain had been developed, largely in the areas of Friendswood and Pearland. While in recent years some attempt has been made to tighten construction standards on new development in the Houston area, runoff has increased and been pushed more rapidly into watersheds, like Clear Creek, diminishing their natural retentive ability to absorb excessive rainfalls. It is this loss of natural floodplains, coupled with the increase in impermeable surfaces and runoff associated with development, that have caused the increased flooding in the Clear Creek watershed.

Flood damage and loss in the area of Clear Creek continue to rise, as evidenced by increases in requests for flood damage assistance from the Federal Emergency Management Agency (FEMA). In 1998, the National Wildlife Federation analyzed the national cumulative FEMA loss payments from 1978 to 1995 for single family homes. Of the 200 homes nationally with the greatest disparity between cumulative FEMA payments and building value, 18 were located in the City of Friendswood, and another 20 were located in other areas of the Clear Creek watershed. Payments of flood losses on these 38 homes exceeded building value of those homes by $4.8 million.

Neither the Corps' alternative nor the HCFCD Plan will effectively reduce flood damages in the Clear Creek watershed, or the FEMA payments associated therewith. Both the Corps' and the HCFCD Plan address the 10-year flood event and do nothing to address flooding related to a 100-year storm event. Both alternatives will also drain additional floodplains within the upper reaches of Clear Creek with the intention of spurring development in those regions. Any further development will ultimately decrease available floodplains needed for floodwater detention, increase runoff entering the Creek—and, in turn, increase the losses to flood damage within the watershed.

Moreover, as previously discussed, flaws in the assumptions underpinning the design of the Corps' alternative render it inadequate to address increased runoff associated with channelization. As a result, the project may actually cause more flooding in the vicinity of Clear Lake. In short, under either structural alternative, the Corps’ $100 million project will not appreciably reduce flood damages in this area in the long-term and may actually increase those damages.

In 1996, as the Corps' construction of the second bay outlet became more visible to the general public, an outcry arose regarding the Clear Creek project. Organizations that opposed the project included the Friends of Clear Creek, Galveston Bay Conservation and Preservation Association, Houston Audubon Society, National Wildlife Federation, Houston Canoe Club, League of Women Voters of Houston, all eight downstream communities, and Galveston County. The National Marine Fisheries Service, Texas Parks and Wildlife, and U.S. Fish and Wildlife Service also voiced concerns about the project. As opposition grew, the Harris County Flood Control District agreed to a six-month restudy. Citizens were optimistic that, through their participation in this process, they would achieve significant changes in the project—expecting the District to develop a plan that balanced the sensitivity of the natural resources of the area with the need to resolve flooding concerns. Unfortunately, the justification for the original project, which consisted solely of the benefits it provided in allowing further development in the Clear Creek floodplain, remained the dominant consideration in the restudy. As a result, minimal changes were made to the original design of the project to preserve some natural areas within the floodplain, and channelization remained the primary methodology of reducing flood impacts. Buyouts of property were considered only to the extent that the project could not be "cost effectively" engineered to preserve all development in the area. The HCFCD Plan has now been presented to the Corps for consideration.

Issuance of the HCFCD Plan again evoked a flurry of opposition, spurred by the realization that this Plan would, like the Corp's proposal, destroy the ecology of Clear Creek, increase flooding downstream, and cost hundreds of millions of dollars. The Corps has now agreed to enter into a restudy of the project. However, in light of Corps' historical reliance on structural flood control and the continuing reliance on future development of the Clear Creek floodplain as economic justification for this project, the potential for achieving a transition from a structural to wholly nonstructural approach is believed to be minimal.

1. Larry Dunbar, A Critical Analysis of Flood Control Proposals for Clear Creek, p. 1-2. (Sugar Land, TX  April 1998)

2. Wendee Holtcamp, "Turbulence Over Clear Creek", Texas Parks and Wildlife Magazine, pp. 12-19 (February 1999).

3. Memo regarding Clear Creek Corridor Habitat Assessment from Ted Hollingsworth, Texas Parks & Wildlife to Woody Woodrow, Texas Parks and Wildlife, September 15, 1997, at p. 1.Id. at p. 18-19.

4. Robert W. McFarlane, The Ecological Roles of the Clear Creek Ecosystem, p. 3-4  (Houston, TX  April 1998

5. Memo regarding Clear Creek Corridor Habitat Assessment from Ted Hollingsworth, Texas Parks & Wildlife to Woody Woodrow, Texas Parks and Wildlife, September 15, 1997, at p. 2.

6. Id.

7. Harris County Flood Control District and Galveston County, Clear Creek Federal Flood Control Project Review, Table VII.9 (December, 1997).

8. Holtcamp, "Turbulence Over Clear Creek," at p. 12-19.

9. Harris County Flood Control District and Galveston County, Clear Creek Federal Flood Control Project Review, Table at p. VII.9.

10. Holtcamp, "Turbulence Over Clear Creek," at p. 16.

11. Id. at p. 19.

12. Dunbar,  A Critical Analysis of Flood Control Proposals for Clear Creek, at p. 4-5.

13. Holtcamp, "Turbulence Over Clear Creek", at p. 17.

14. Memo regarding Clear Creek Corridor Habitat Assessment from Ted Hollingsworth, Texas Parks & Wildlife to Woody Woodrow, Texas Parks and Wildlife, September 15, 1997, at p. 2.

15. McFarlane, The Ecological Roles of the Clear Creek Ecosystem, at. p. 5.

16. Dunbar, A Critical Analysis of Flood Control Proposals for Clear Creek, at p. 4.

17. Id. at p. 5.

18. Id.

19. See generally, National Wildlife Federation, Higher Ground: A Report on Voluntary Buyouts in the Nation’s Floodplains (Washington, D.C. July 1998).

20. Memorandum from Franklin D. Raines, Director, Office of Management and Budget and Kathleen A. McGinty, Chair, Council on Environmental Quality to Federal Agencies regarding Floodplain Management and Procedures for Evaluation and Review of Levee and Associated Restoration Projects (“1997 Guidance”), February 18, 1997.  The 1997 Guidance was issued to assist the floodplain and levee restoration projects necessitated by the floods of 1996 and 1997.  It embodies the lessons learned and policies established over the past four years. As a result, its mandates also must be applied to the selection and implementation of new, non-emergency, flood control measures.

21. 1997 Guidance at p 2.  The Corps’ own study of the Midwest floods of 1993 recommends, among other things, a shift in emphasis to nonstructural flood control measures, including the use of natural floodwater storage areas such as wetlands and floodplains, and restricting development in flood prone areas. See generally, U.S. Army Corps of Engineers, Floodplain Management Assessment of the Upper Mississippi River and Lower Missouri Rivers and Tributaries (St. Louis, MO  June, 1995).

22. 1997 Guidance at p.1.

23. Dunbar,  A Critical Analysis of Flood Control Proposals for Clear Creek, at p. 6-7.

24. U.S. Army Corps of Engineers, Floodplain Management Assessment of the Upper Mississippi River and Lower Missouri Rivers and Tributaries.

25. Interagency Floodplain Management Review Committee, Sharing the Challenge: Floodplain Management into the 21^st Century, Preliminary Report of the Scientific Assessment and Strategy Team Report of the Interagency Floodplain Management Task Force and Executive Summary  (Washington, D.C. June, 1994).

26. Dunbar,  A Critical Analysis of Flood Control Proposals for Clear Creek, at p. 2.

27. National Wildlife Federation, Higher Ground: A Report on Voluntary Buyouts in the Nation’s Floodplains at p. 157-159.

28. Id. at pp. 92-93, 155-159.

29. Holtcamp, “Turbulence Over Clear Creek,” at p. 16.  In May 13, 1997 Andrew Samson, Executive Director of the Texas Park & Wildlife Department, forwarded a letter to Colonel Eric Potts, Galveston District, U.S. Army Corps of Engineers, stating his agencies concern that " the benefits that the stream and riparian habitat provide will be virtually eliminated by a project that is based on standards of practice that were outdated decades ago. Modern approaches and techniques that provide floodplain protection… should be considered."  Mr. Samson requested that the Corps revisit the project in light of changes in approaches to flood control that had occurred since authorization of the project.

30. Holtcamp, "Turbulence Over Clear Creek", at p. 12-19.

31. Id. at p. 16-17; Dunbar, A Critical Analysis of Flood Control Proposals for Clear Creek, at p. 3-4.