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No Water - No Wonder!
Lee Walton

Mercy! The "Acropolis" sure "ducked a bullet" Friday evening, March 31st. For almost four hours, over 400,000 Charleston CPW customers, thousands of tourist and almost 40,000 Bridge Runners found out what it's like to live without water - Third-world style. Charleston's Assistant Fire Chief Joe Schofield best described this shocking "wake-up call" in his quote published in the Palter & Chatter - "There's no water anywhere in Charleston." How would they have ever fought a major fire downtown?

How did this happen in a modern metropolitan area of over 600,000 people? A person with technical knowledge explained it this way: Like our own bodies, a municipal water system uses pumps and piping to keep water flowing at the required quantity and pressure. When a rupture occurs in a critical water main, massive losses of water and pressure rapidly occur. If we suffer a major hemorrhage that cannot be quickly controlled, we go into shock and bleed to death. The same thing happened to Charleston CPW's water system on March 31st when its "aorta" hemorrhaged. For several agonizing hours, the greater Charleston area and surrounding islands had a municipal water system that had actually "bled to death".

The problem started several months ago when the 22-year old "aorta" of CPW's water system began to shift sideways out of alignment over a pile-supported tidal creek crossing. CPW engineers monitored the problem and planned to replace this largest water main in their system during a future $180 million upgrade project. Unfortunately, they underestimated the seriousness of the danger and took no immediate corrective action; CPW gambled for more time and lost. Increased system demand generated by an ongoing drought and several large tourist events in the Charleston area required higher than normal operation pressures. As this large main began to deflect sideways at a few joints, there was nothing of substance to stop the progressive, rapidly escalating failure caused by the increased lateral water pressure acting on the failing joint. Once the main shifted sufficiently out of alignment, there wasn't enough lateral resistance from the support piling to prevent the pipe from deflecting even further - joint failure was inevitable.

How did CPW stop the "hemorrhage"? To their credit, correctly, by keeping just enough pressure on the rupture to prevent a total loss of system pressure while rerouting flow through smaller mains to isolate the failure. CPW was very lucky; the failure could have been even more catastrophic. Had the pipe joint completely blown apart, the entire distribution system and remote storage tanks would have rapidly "back-flowed" into the open breach before preventative measures could have stopped a total system collapse. No amount of rationalization and "spin" by J. "Pericles" Riley or CPW would have saved the Charleston Fire Department's prized "ISO Number 1 Rating" had such a massive failure occurred.

A change in CPW's water storage "philosophy" a few decades ago also contributed to this system-wide failure. They removed several large elevated storage tanks and replaced them with fewer, smaller ground level tanks. As CPW reduced the amount of remote water storage, they became more dependent upon centralized treatment and pumping capacity to meet ever-increasing demand. The results of these decisions are why CPW cannot now quickly isolate parts of its system and temporarily supply them from remote water storage tanks. When a "bleed" occurs now, the whole system is degraded. Even more surprisingly, both North Charleston and the Charleston Peninsula are almost totally without adequate water storage tanks. State water supply regulations normally require that a municipal system provide a water storage capacity equal to at least one-half of the maximum daily water consumption. Unfortunately, Charleston CPW chose a different path that exacerbated the recent system-wide failure.

CPW's reliance upon its centralized supply and pumping system could also cost Charleston dearly if an earthquake similar to 1886 event reoccurs. It would snap underground water mains and gas mains like "match sticks". Recovery from such a wide spread disaster would be lengthy and at considerable risk to the Charleston metropolitan area. As a reminder, it wasn't just the earthquake that destroyed San Francisco a century ago; it was the damage to its public water system and the uncontrollable, gas-fed citywide fires that followed.

Charleston CPW should heed the lessons learned from this recent "wake-up call", significantly increase its system-wide water storage and provide additional transmission main redundancy. It's also past time for "Pericles" to start thinking about the survivability of our community and not the next monument for his "Acropolis."

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