About 10 miles of Saipan’s sewer mains, mostly AC pipes, were installed almost 40 years ago and are beginning to fail, he said.
Three pipe collapses have already occurred in Chalan Kanoa, Chalan Kiya and As Terlaje, he added.
Instead of just replacing the single pipe length that failed, the entire stretch between manholes is being replaced by local contractors, Malae said.
He added that two other failures occurred one week after the other in Puerto Rico.
Unlike the sewer main collapses, the leaks of up to 300 gallons per minute occurred on a 16-inch metal fitting that joined three 15 inch pipes, he said.
“Because these are emergency replacements over a short span, rather than a planned replacement of long stretches of main, the cost is about double per lineal foot,” he added.
The cost is close to quarter of a million dollars, he said. “We have no sewer rates to recover those costs so we are asking the various CIP funding sources for help.”
The crown of the pipe has thinned out over the estimated 10 miles of mostly 10-inch pipes, he said, adding that besides old age, the thinning out was accelerated by the sulfuric acid erosion of the unwetted diameter.
To extend pipe lifespan, acid resistant materials such as lined PVC must be used, he said.
The fitting installed in 1993 was improvised in order to connect the three non-standard pipes, Malae said.
Non-standard pipes coupled with improvised fittings without a realistic maintenance budget are a formula for premature failure, he added.
“You can only marvel at what the wastewater crews are able to accomplish in the field given such shameful conditions that are not of their doing,” he said.
Malae said given the resources available, CUC is resolved to set priorities and address the issues one by one.
This week, he added, CUC is about to award a contract to rehabilitate the Sadog Tasi Wastewater Treatment Plant which was designed to be a secondary treatment facility just like the other plant at Agingan.
He said Saipan is required secondary treatment, but Guam and American Samoa enjoy a waiver from the Environmental Protection Agency that allows primary treatment which is cheaper to build and operate.
Malae said CUC will soon receive some relief from the U.S. Department of the Interior’s 702 capital improvement funds for the fiscal year 2010.
The funding, he added, will allow for the rehabilitation of the Agingan Wastewater Treatment Plant, supplementing the Sadog Tasi rehabilitation and the replacement of the collapsing sewer mains’ one fitful pipe length.
He said the other sources of capital help are expected and available from the American Recovery and Reinvestment Act, the Economic Development Act and Federal Emergency Management Agency.
