How Do We Handle Another Allison?
First Draft of Flood Protection Plan to be Completed in September

It's easy to ask and exceedingly difficult to answer. It's the question on the minds of many, almost three months after floodwaters from Tropical Storm Allison added a new chapter to the history of the Texas Medical Center.

"How can we protect ourselves from this type of flooding in the future?" is the question being posed by employees in cafeteria lunchrooms, top-level managers at institutional meetings, and students returning to classes this fall.

To provide expertise in arriving at an answer, the Texas Medical Center has enlisted support from Skidmore, Owings & Merrill LLP, the same firm that helped draft the Master Plan for the Texas Medical Center in 1999 - a campus-wide plan that sets forth a vision for growth in the Texas Medical Center over the next 50 years.

"Collaboration among all 42 Texas Medical Center institutions has been an ongoing goal of the Texas Medical Center leadership, so that the entire campus functions as one cohesive entity. Parking, traffic flow, land development, and the skybridge network have all been hot topics," said Adam Thies, project manager at Skidmore, Owings & Merrill.

Now, on behalf of the Texas Medical Center, the firm is looking at yet another issue - flood control. A plan that will develop options for improved flood control in the future is "in the works."

The plan, with a first draft slated for completion at the end of September, is titled the "TMC Hazard Mitigation Master Plan." Texas Medical Center institutions are currently involved in developing this draft as well as participating in the ongoing process to finalize the plan.

Mitigation means "to alleviate" or "to bring relief to," and that is precisely the point of the anticipated plan - to offer suggestions about how to lessen the impact of similar flooding in the Texas Medical Center in the future.

After seeking input from a wide range of professionals including flood experts and hydrologists who study how water is distributed and circulated; administrators; researchers; and subsidence, utilities, and engineering professionals with knowledge of Houston-related flood issues, and studying how other communities handle similar incidences, the Texas Medical Center, with assistance from Skidmore Owings & Merrill, has opted to approach the challenge from three different, but related, perspectives.

The first phase of the hazard mitigation plan will look at the institution-to-institution interactions in the Texas Medical Center, with an eye toward a stronger passive flood protection approach.

Passive flood control measures, Thies explained, are built in, are in place all the time, and require no action on the part of anyone when a flood threatens.

"Relocating electrical and telecommunications switch rooms to higher levels within a building is a passive strategy," he said. "Once the switch rooms are up higher, the likelihood of flooding is greatly diminished."

Active flood control measures are those that require some sort of action from a human being when flood conditions threaten. For example, a manually operated flood door is an active control because "a human must shut the door to make it work," explained Thies.

Passive strategies have definite advantages over active ones, he said, especially with a storm like Allison.

"The rains began deluging the Texas Medical Center at midnight on a Friday, when staffing was at a minimum. Calling employees at home, at that hour, on a weekend, as four inches of rain an hour began inundating the area, resulted in employees being flooded out on Houston streets before they could get here, and posed a safety threat to them as well," Thies said. "Passive strategies would require minimal, if any, human action."

The next two phases of the plan will examine the "bigger picture" - not only issues pertaining to Texas Medical Center institutions, but also characteristics in the community that play a part in how water drains through the Texas Medical Center campus.

Phase Two will evaluate how proposed flood control measures in the Texas Medical Center would affect neighboring residential communities, Rice University, Hermann Park, and the Texas Medical Center's quickly growing South Campus, encompassing the area south of Braeswood toward the Astrodome and 610 Loop. Any flood mitigation measures the Texas Medical Center adopts cannot, by law, cause flooding to neighboring communities, just as flood measures enacted by those communities cannot cause flooding to the Texas Medical Center.

Phase Three will pay close attention to the entire Brays Bayou watershed (surrounding lands that drain water into Brays Bayou), the Harris Gully culverts (two underground concrete box culverts that carry rain and runoff water from neighborhoods north of Highway 59 under the Texas Medical Center, and ultimately into Brays Bayou) and how the dynamics of this drainage system affect flooding in the Texas Medical Center.

All this is being done in the context of three questions, Thies said: 1) How can we improve the traditional stormwater management system that uses technology such as underground pipes and the Harris Gully culverts? 2) How do we plan for overflow of stormwater when that system receives too much water? 3) What is our emergency plan when water is at the front door?"

While this plan alone won't "solve" the problem of flooding in the Texas Medical Center area, it will provide a start toward what ultimately will be a city, county, and federal effort," said Andrew Icken, Texas Medical Center executive vice president.

"Because the flow and distribution of stormwater in the Texas Medical Center is affected by areas outside the Texas Medical Center campus, we can't create a plan in a `vacuum.' We'll need to involve many entities at all levels of government to look at the complete picture. The Texas Medical Center is one very important piece of a very large picture," said Icken.

Among the groups involved are the Harris County Subsidence District; the Army Corps of Engineers; the Harris County Flood Control District; the Federal Emergency Management Agency; and neighborhood, community and civic groups.

At a hydrology and flood control workshop held Aug. 6 and 7, a number of "things to think about" were proposed, and will be followed up on in future meetings. These measures may be adopted as part of the final "Hazard Mitigation Master Plan." Several of the proposed measures involve the Harris Gully culverts and Brays Bayou.

"Brays Bayou didn't `cause' the flooding in the Texas Medical Center," Thies said. "Flooding occurred because water from north of Highway 59 attempted to drain through the Harris Gully culverts into Brays Bayou, but because the bayou was already full, the Harris Gully water `backed up' into the Texas Medical Center."

Keeping this in mind, some of the water from the Harris Gully culverts could be rerouted, or the water flow and pressure in the culverts could be reduced, Thies said.

Another suggestion involves incorporating more green space into the Texas Medical Center campus and surrounding areas.

"The Texas Medical Center is composed largely of concrete and asphalt, and neither absorbs rainwater. Natural areas, however, soak up rainwater and alleviate flooding, Thies explained.

Then there's the process of coming up with an elevation that dictates how high above sea level new or reconstructed buildings should be built. The Texas Medical Center Corp. is currently coordinating this discussion with the Federal Emergency Management Agency, state of Texas and city of Houston officials, and many engineering professionals. To complete this task, studies of Brays Bayou and the Harris Gully are under way. Until they are completed, discussions related to an "interim elevation" where all parties agree, need to occur, Thies said.

And there is no guarantee that the elevation settled upon will protect buildings from flooding in the future.

"Twenty miles from the Texas Medical Center in the eastern part of Harris County, the floodwaters were high enough to be classified at unbelievable flood plain levels," Theis said. "So building at the standard 100-year or 500-year flood plain levels in that area of town probably wouldn't have helped."

"One thing is certain," Thies said. "We can't control nature. We can install flood doors and gates, put out sandbags, move our utilities above ground, but the issue is bigger, much bigger. We all must look at the entire picture ... examine why water is draining from other Houston areas into the Texas Medical Center, then decide together how best to handle the situation for the good of all. How one institution rebuilds may affect the institution next to it, and how TMC's neighbors such as Rice University and Hermann Park conduct their activities will also have an impact on the TMC campus.

And while the initial TMC Hazard Mitigation Plan will not be completed until late September, hurricane season is here now, cautioned Dr. Richard E. Wainerdi, president and CEO of the Texas Medical Center.

"Institutions in the Texas Medical Center must be prepared to take steps today to mitigate the effects of foul weather," he said.

The process leading up to a finalized hazard mitigation plan will be a thorough, comprehensive and coordinated effort," Dr. Wainerdi said. "Our efforts must take into account not only the Texas Medical Center, but also our neighbors and our local, state and federal governments. We must look beyond our own front door, and concentrate on the bigger picture to be successful."

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©2006 Texas Medical Center

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