Ames has water service again
August 16, 2010
The city of Ames was able to return its water system to full service
yesterday, after several days of work to repair broken water mains and some frustrations with non-compliance by residents
who were told to conserve water rather than using it. The system had to be shut down on Wednesday
due to a large number of water-main breaks that led to contamination concerns. Mason City
lost its water service in 2008, and Des Moines
experienced the same in 1993; both of those other system outages were caused by flooding that contaminated the water-treatment plants in those cities. Ames had a different cause, but roughly the same effect.
The reason it can take so long to return a municipal water system
to service after an outage is that everything needs to take place in stages. First, if the plant itself has been flooded, the floodwaters have to be stopped and removed.
Second, the equipment inside the plant has to be dried out -- motors and control systems obviously cannot be run on electricity while they're still wet.
Third, the plant itself needs to be disinfected, since floodwaters contain all sorts of contaminants that make them unsafe for consumption. That process often takes another day or more, inclusive of cleaning the flood debris (like mud and silt) from the equipment and drying or replacing the electrical components that were flooded.
Fourth -- and this is the part that most people probably don't realize -- the distribution system must be disinfected. Depending upon the size of a city's distribution network, the water that comes out of a tap in a far corner of the city may have spent a number of days traveling from the plant into booster pump systems
and up into elevated storage tanks (water towers), before traveling out of storage and through water mains to neighborhood distribution pipes and into the home.
Ames is (relatively) fortunate in that only the distribution system was damaged by the floods -- not the plant itself. That sped the recovery effort by at least two or three days. But an epic event like this flood and the five days Ames spent with its system in shutdown should stay at the top of customers' minds all over the country the next time a municipal water system asks for a modest rate increase to help pay for system improvements and upgrades. Ratepayers are often much too quick to bristle at the suggestion that water isn't free and that system upgrades will cost more each month. The few but difficult days that Ames spent without water should remind people of the tremendous value that municipal water brings to everyday life, at a relatively tiny cost. Ames city employees should be applauded for their efforts to bring essential service back on-line in swift fashion.
last revised August 2010