JANUARY 27, 1997
by Jeff Switzer
WOODINVILLE--A certified arborist will soon finish evaluating the London plane trees along 140th Avenue NE, with removal and replacement of the trees planned for the summer along with restoration of the damaged roadway.
The trees, as many as 69 near the BP Gas Station and Seafirst Bank, have gradually damaged the road, gutters, and sidewalks. Given that the trees could grow to as large as 36 inches in diameter, city staff have recommended expert evaluation of the trees. They plan to replace only the guilty ones or those interfering with overhead power lines. As many as three other varieties may be used as replacements.
Along with new trees will come restoration of one of the city's busiest intersections. The City Council recently authorized the improvements to the NE 175th Street and 140th Avenue NE intersection to include a cement middle area, rather than asphalt, for an extra $100,000. Asphalt would have lasted for about eight years; the cement will be good for as many as 40 years.
The city discussed using a mold for the cement similar to what TRF is planning for the Target shopping center, where a variety of leaves are depicted in relief.
But the trees haven't been the only culprits damaging the roadway. Regular traffic from heavy buses at the intersection has "kneaded" the asphalt, which is especially damaging during the hot summer months. The city does not plan to widen any of the road sections.
The damage to the asphalt has also begun to impair the induction loops, which signal the traffic lights when a car is in the cueing area. Each loop costs $600, and at least one is known to be faulty.
The next step in the project is an informational workshop for the public, planned for Feb. 13 from 5 p.m. to 7 p.m. in the Council Chambers, 13203 NE 175th Street. In mid-March, the city will advertise for bids, followed by removal of the damaging trees in mid-April. Road construction is expected to begin in mid-June.
'Distressed but strong'
The trees, described as "distressed, but growing well" in spite of the limited growing space, are the subject of creative tree-planting scenarios.
One suggestion is to excavate a sufficiently large area with easier soils in certain directions to encourage the root system to develop in a controlled fashion. Spacing and staggering, as well as planting a variety of trees, have also been suggested, to prevent the lot of them from dying off if only some became diseased. Tree grates are also something for the future, possibly with a distinctive Woodinville design.
The nine trees north of the BP gas station are back far enough and in a wide enough planting strip to remain, and the city also hopes to work around the three evergreens at 7-11.
Last fall, Molly Beck, a certified consulting arborist and Tree Board member, said the London planes have been planted all over and are causing problems to other cities besides Woodinville.
"They're widely thought of as a hearty urban tree, able to survive in poor soils and pollution," she said. "But they were planted without consideration of the effects." The trees were 15 to 17 feet tall with the potential to reach heights of 60 to 80 feet when planted under utility wires during the King County days.
When the city begins looking at the alternatives, Beck says a number of courses of action can be taken, including retention, replacement, and novel engineering approaches to the problems.
"But in some cases, there is no choice. Where utility wires are concerned, it's unfortunate that the wrong tree was chosen," Beck said.
In summer of 1993, three months after incorporation, a pedestrian was crossing the street from 7-11 to Seafirst when, after being distracted by a loud vehicle, she tripped over a raised section of sidewalk caused by the roots of the trees, falling and breaking her hip. That claim has yet to be settled with the city and remains open.
Since then, the city has installed concrete ramps to prevent pedestrian hazards, though the surface remains uneven and the city's insurance has instructed the city to replace the sidewalks.