First the good news: The people at Tampa Bay Water say the cracks in the cement lining of the 14-story reservoir in south Hillsborough County — some of which ran the length of a football field — are not a safety issue. That must be some relief to residents near the 1,000-acre bowl that currently holds about 6-billion gallons of water, or roughly 14 times the volume of Raymond James Stadium. Yet the cement lining is but four years old. Any fix is years away and could cost millions of dollars. Not only will the reservoir limp along until then, playing a fraction of the role it is supposed to play in supplying the region with water, but the cracking might be caused by normal operation. The implications, in other words, could get worse.
How did this happen and who at Tampa Bay Water will be held responsible? The utility's board has voted to sue the three companies responsible for building the $146-million reservoir. But where was the oversight at the utility that should have spared the agency another black mark and the region from being unprepared to enter the dry winter season?
The cracks in an interior layer of the wall were discovered in 2006. They are on the upper portion, run horizontally and extend up to several hundred feet. Officials have spent two years and $700,000 to research the problem, and they will continue to monitor and fill any cracks until engineers propose a permanent solution. In the meantime, the three-county utility will not increase the water level in the reservoir beyond where it is now, at half capacity. The reservoir might run at half speed until at least 2010.
Tampa Bay Water insists the reservoir is safe. The reservoir wall is formed from a mixture of soil and cement. Its primary purpose is not to retain the water, but to support the earthen embankment that forms the reservoir bowl, which itself exists to protect an impermeable membrane, which is embedded along the perimeter of the reservoir. As the reservoir is filled, water passes through the cement wall up to the membrane. Tampa Bay Water said the cracks are caused when the water is drawn down, by the pressure as water escapes the embankment and pushes back through the cement wall. Officials theorize that is why the cracks are generally found along the upper elevations where water was held.
Tampa Bay Water may feel it is getting a grip on the engineering, and it may find political cover in suing the contractors. But running the reservoir at half capacity is not a loss that can be viewed in isolation. The whole point of the reservoir — the whole point of Tampa Bay Water — is to act as part of an integrated system for developing and supplying water to the region.
During the summer rainy season, the utility skims water from the Alafia and Hillsborough rivers and the Tampa Bypass Canal and stores the water in the reservoir for the dry months. Tampa Bay Water said it is confident that operating the reservoir at half capacity will not force it to increase groundwater pumping, but the reality is that billions of gallons of water have been lost as a resource, leaving the region much more dependent on rain, on keeping the desalination plant running at capacity and on the faithfulness of residents to conserve.
This is the second major project by Tampa Bay Water that has taxed the region's patience. Problems with the desalination plant soured the political climate to build another. Now the public sees a problem at the reservoir and hears many of the same assurances — even as a second reservoir is on the table.
The reservoir is invaluable; it conserves water, protects the environment and helps stave off drought. It needs to be not only part of our water strategy but also sound and reliable. Tampa Bay Water needs to move beyond lawsuits and excuses and start reassuring the public of its abilities to manage this precious resource. It needs either more expertise or more hands-on management, and it needs it quick.