Arbor Heights water-main improvements to start soon

By Tracy Record
West Seattle Blog editor

The city’s work to replace undersized water mains in Arbor Heights – a problem spotlighted by water-supply trouble during a house fire last August – is expected to start this month.

That’s part of what Seattle Public Utilities told more than 60 residents who gathered for a community briefing/Q-A session last week at Arbor Heights Community Church, barely a block from the home that burned August 27th.

The first work will be on a relatively small stretch along Roxbury:

But the rest of it – see the full map here – won’t happen until this fall. Why the gap? That’s part of what was explained.

The meeting was far more cordial than contentious, and even ended with applause. On hand for presentations and questions were about half a dozen reps from SPU – which is accountable for the water system, including fire hydrants – and the Seattle Fire Department, which is accountable for testing each of the city’s 18,000 hydrants annually, though their testing only goes far enough to make sure they can be turned on.

The underlying – literally – problem for Arbor Heights is an underlying one: The size of the water mains.

Parts of Arbor Heights have 2- and 4-inch-wide water mains dating back to the ’30s; the area was not annexed to the city till the early ’50s. Senior civil engineer John Ford from SPU presented some of the “how did things get to be this way?” history for starters. The area was part of King County Water District #3 and “had different standards,” he explained; most of the north/south mains are 4-inch-wide cast iron, while most of the east/west mains are 2-inch galvanized steel, and the bulk of the system was built in 1939, aside from additions by developers. The exceptions are 8-inch cast-iron mains along 39th and 100th. (At California/100th, for example, there’s a fire flow of more than the 1,000 gallons-per-minute standard.)

The water-main situation was no secret when Seattle annexed the area more than half a century ago, but improvements were usually made through residents approving a Local Improvement District to tax themselves to raise the money. Twice it went to voters, twice it was turned down. (“So we just kind of got forgotten about” after that? asked one woman, who identified herself as the wife of “the one with the garden hose there fighting the (August) fire … I don’t want to see my husband fighting a fire with a garden hose again.”)

These improvements are NOT through any kind of district – they’re being paid for by the city, it was reiterated when anther attendee asked how much extra they would be paying, and was reassured that SPU has “found” the funding without an assessment, as they did for the first round of improvements they decided to make after the August fire-flow shortfall – 12 new fire hydrants, all but one of them replacing smaller “village fire hydrants.” A picture comparing old (below left) and new was displayed at the meeting:

The older, smaller hydrants were all on bigger water mains anyway, so this just improved access to what existed before. The 12th hydrant is a brand-new one added to a 12-inch main at 35th and 107th, Ford said.

As SPU had explained to the Seattle City Council in a December briefing on the August fire aftermath – WSB coverage here – the goal for the project is to make sure that no property in Arbor Heights is more than 1,000 feet away from a hydrant with a “fire flow” of at least a thousand gallons per minute. That’s the standard for single-family-home neighborhoods, according to SPU, and Arbor Heights is 97 percent single-family zoning.

Some were concerned about water pressure for homes, not just “fire flow.” Ford explained that pressure isn’t really the issue here – Arbor Heights is doing OK on that front already, and the smaller mains are actually “a constriction.” After the work is done, he said, “you might even find higher pressure upstream because there’s less restriction downstream.” (Already, attendees were told, the available fire flow in the area in general is up 25 percent, just with the hydrant changes.)

Even if old mains are big enough, it was asked, what’s the time frame for replacing them? Ford revealed that it depends on how corrosive the soil is in a given area, and in Arbor Heights, the answer is “not very” – in Seward Park, for example, some “thick-walled cast-iron mains installed in 1890” may have another century of usability left.

The presentation moved on to more specifics. Project manager Joe Herold explained that most work would be on the north or east side of a street, with a 2-foot-wide trench, about 3-feet deep, and an 8-inch main would be installed.

If you’re in an area that will be affected, you’ll get a notice of when your water will be shut down for the work to happen. The first place, Herold said, would be a 75-foot stretch along Roxbury near Fauntleroy Park, perhaps as soon as two weeks away. That area also will see a “village hydrant” replaced with a new standard one. Then the rest of the new mains will be installed in November and December. Why not till then? “A lot more design work is involved,” Herold said, saying the design is at the “30 percent” level now, and they still need permits as well as going out to bid.

Once they get to that part of the project, he said, SW 102nd will also get six new hydrants on the north side of the street as well as “retirement of the existing village hydrants on side streets” to the north. (The end result is laid out on this map.)

39th SW will get one new hydrant and will see the “village hydrant” at 39th/99th retired; the new one will move “around the corner” to be on the new main on 39th.

California SW will get a new water main from 98th to 100th, an 8-inch main mostly on the east side of the street.

SW 105th next to Arbor Heights Elementary School will get one new hydrant and a replacement for an existing two-inch line. However, the school itself is “fed off 104th,” SPU reps said, and is NOT expected to lose water at any point during the construction process.

As for everyone else – if you are “along or adjacent to” the streets affected, you “will experience up to 3 water-main shutdowns,” since it’s a three-step process (though the shorter segment on Roxbury may be more like one or two). Many concerns were voiced about some homes not getting advance warning during the shutdowns related to the recent hydrant replacements, and SPU promised to do a better job, saying the shutdowns generally would be during “business hours,” and would last no longer than “several hours.” Unlike the hydrant-work timeframe, they said, there’s more time before this work to test “shutdown blocks” so they know more precisely who will be affected by which shutdown. (One woman with a home business said this still sounds like a potential hardship for her, so SPU invited her to talk with them about how best to coordinate a plan.) In addition to general advance alerts, individual residences are supposed to get door hangers with 72-hour notice of a shutdown.

Other ways the work will affect the neighborhood: Some temporary no-parking signs, traffic re-routing, and “slightly larger hole(s)” in intersections where “legs” of the water system would have to be connected. What if you have trees hanging over a potential work zone? one attendee asked. Answer: If the tree branches are at least 14 feet over the street, a backhoe can get under them. (“They’re not,” said the man.) Other complications can ensue, but the job pace will usually be about 100 feet a day. Herold said “one short segment (would be) open at a time for a few hours,” then they’ll backfill as they go along – if something will need to be dealt with twice, it may have a metal plate over it until it’s ready to be backfilled. Final “road restoration” work will be weather-dependent.

Then there was the big question someone finally dared to ask.

“What happens if God forbid we have another fire?”

SFD assistant chief Michael Walsh: “We’ll adjust, and we’ll move on to the nearest hydrant [with appropriate fire flow] … we’re working very closely with the Water Department on the redesign, and will take it into account in our tactical decisions.”

P.S. Trivia point – someone wondered if water-main breaks were a factor in this at all, and was told, no, no breaks lately, and systemwide, the entire city sees 141 a year.

P.P.S. Anyone in Arbor Heights with questions was invited to contact Joe Herold, project manager, directly – joseph.herold@seattle.gov or 206-386-9857. SPU says it’s not planning any other public meetings before or during the project, “unless there’s a need.”

2 Replies to "Arbor Heights water-main improvements to start soon"

  • Steve February 2, 2012 (9:43 am)

    I was driving by 63rd and Admiral a couple of days ago and saw some city workers testing a hydrant on the NE corner. A weak flow of brown water was coming out. Do we have the same trouble on Alki Point as in Arbor Heights?

  • DC February 3, 2012 (5:10 pm)

    They already have been doing some preliminary work on the Roxbury hydrant/water main for the last 3 days. No notice has been given about water being shut down yet (and we heven’t lost our water supply at all yet), but the road has been closed while they have been working on it- so traffic has to backtrack around that 2 block stretch while they are working.

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