Along the border of the United States and Mexico, Laredo has been a major beneficiary of growth from the North American Free Trade Agreement. As much as 38 percent of trade between the two nations travels through this South Texas city of about 180,000. Despite this benefit, growth pressures have seriously affected its quality of life.
The increase in international commerce provided explosive development and growth in the 1990s. But it also strained Laredo's resources, including the city's recreational and environmental management facilities.
Located in the eastern half of the city, Chacon Creek originates north of Lake Casa Blanca and flows about five miles to the south and west before emptying into the Rio Grande. The creek is a tremendous natural resource for Laredo with economic, recreational and educational potential; but this potential has historically been masked by neglect, dumped materials, and debris.
Additionally, increases in urban development have changed the hydrology and hydraulics of Chacon Creek, resulting in an increase in flood flow and expanding the 100-year floodplain.
"Due to rapid growth, many cities are scrambling to find open space and park land for recreational facilities, and what they're finding is that many times the only space available is in the floodplain," says Tony Trollope, project engineer for Carter & Burgess. "Chacon Creek is a case in point. It has been neglected for years and is only now being looked at as a great recreational and educational opportunity for the city."
Carter & Burgess prepared a multi-objective master plan, which defined the creek's 100-year floodplain, proposed targeted channel improvements to relieve flooding, maintained the overall natural character of the waterway, and added needed passive/active recreation facilities. Rather than build a 200-foot-wide concrete channel over the entire 4.5 miles of the corridor (previous city study), Carter & Burgess proposed targeted terraced channel enlargements over a much shorter distance, less than 4,000 feet, which would accentuate green spaces, preserve the creek's natural course, minimize impact on wildlife and wetlands while providing the most cost effective flood mitigation. These channel improvements require the removal of approximately 50 homes located in the 100-year flood plain. However, upon completion of the proposed improvements the reduction in 100-year floodplain elevation will remove approximately 250 homes from the floodplain. Workshops and public hearings provided for community involvement and helped answer citizens' questions about the master plan and other issues while including the public in the design process.
Carter & Burgess' strategy also addressed leisure and cleanup issues. Laredo city leaders envisioned the creek offering recreational, educational and economic opportunities. Carter & Burgess developed a multiple-objective approach that would create "people spaces" and develop amenities, including a hike and bike trail system and a regional park. The plan also emphasized ecosystem restoration to transform a once-abandoned area littered with tires, barrels and pallets into a year-round attraction for citizens and visitors.
"Chacon Creek is a prime example of the good things engineers and urban planners are trying to do with urban watersheds," says Tom Mountz, Chacon Creek project manager for Carter & Burgess. "It's a good mix of all the elements - some public space planning, some hazardous material handling, some sensitive wetland areas, some flood plain control. The challenge is to find solutions to several problems at the same time while benefiting everyone in Laredo."
And do it at minimal cost. Carter & Burgess' multiple-objective approach allowed Laredo to pursue grant monies from multiple sources. "There's not much funding just for flood control anymore," says Mountz. "Most of the projects that are funded now are multiple-objective projects." Carter & Burgess sought funding from Texas Parks & Wildlife Department, Army Corp of Engineers and other sources.
"It seems to be working. Scientists and engineers are involved, the city is involved, the people are involved," Mountz says. "We're providing a viable alternative to a 200-foot-wide concrete channel that would cost a lot of money and only help in flood control. After all, the creek needs to be a useable part of the city's fabric when it's not flooding." And that makes sense for everyone.
(Prepared by Rick Waters of the Carter & Burgess engineering firm.)