Good weather and corroded water pipes have caused a delay in the city’s annual water line flushing. Water Utility Superintendent Dave Crabtree said work will not be completed until September 14.
Water crews this summer also have been painting reservoirs in the Mendenhall Valley and Lemon Creek, so line flushing stopped last week when Juneau’s snotty weather finally got better.
“There was a break in the weather. We had to get the water out of the east valley tank for the painting contractor, so we had to re-evaluate our priorities and get them painting on the tank, which put the kibosh on our plans to perform our flush of the distribution system,” Crabtree said.
When road work on Second Street in Douglas revealed a corroding water system, water utility staff also had to resolve that issue, which took a couple of days, Crabtree said. So line flushing begins again on Monday at the area of the “hospital to Cohen (Drive), airport distribution area, and a core part of the mid-valley and Back Loop.”
The flushing may cause some water discoloration or minor disruption in service. If water is discolored, wait until crews have finished their work, then run the cold tap until the water runs clear.
Meanwhile, replacing the Douglas water pipes will cost the city $375,000. The original project was roadway resurfacing, replacing fire hydrants, culverts and a sewer manhole. But a crew working on a fire hydrant found a severely corroded water main made of different materials than city records show.
It was built in the 1980s and expected to last 50 years. But according to CBJ Acting Engineering Director John Bohan, even the state-of-the-art ductile iron pipe is beyond its useful life.
“One of the pipes we found in Second Street in Douglas was cast iron, which was the original old style pipe,” Bohan said. “We had a cast iron and a ductile, which our as built showed the location but not the material correctly. They called them ductile iron pipes. The ductile iron pipe was actually being eaten away by electrolysis as well. So aside from the as-built issue of the mid-80s we have a bigger scenario of electrolysis on the newer pipe, so we’re going to have to react, or we’re going to have problems.”
Bohan explained the problem to the Juneau Assembly earlier this week, which approved the funds to replace the water system. The discussion prompted member Ruth Danner to ask a key question:
“How much of our water system is in this state?”
Bohan said the Douglas Island water system appears to have more problems than other parts of the borough. He said city engineers don’t “have a good handle on what’s causing the corrosion.”
“We know a lot of the materials that went in in the mid-80s and we’re finding our problem areas,” he said. “We’re not in trouble per se, but we do have to start thinking about water infrastructure as it’s coming up to its useful life span.”
Admiralty Construction has been awarded the contract to replace the Second Street water main.
Water Utility Director Crabtree says homes and businesses hooked to the system will not experience any disruption in service while it’s being rebuilt.