WHAT: A project to repair and replace 1,300 linear-feet of damaged sidewalk along a one-block section of Sixth Avenue and Sixth Street begins this spring and will be complete by summer. Kirkland’s Sidewalk Maintenance Program will restore a uniform sidewalk along both sides of the neighborhood streets.
WHAT TO EXPECT: To restore the sidewalk and ensure its longevity, Kirkland’s prospective contractor must first remove 29 trees that are in the City’s right-of-way. Kirkland will replace nine of those trees during sidewalk construction.
The Public Works Department maintains hundreds of miles of sidewalk within the City using two available funding sources - the Street Operating Fund and the Capital Improvement Program (CIP).
A number of factors cause sidewalk damage. The primary cause is from tree roots pushing up on concrete sidewalk panels which cause "offsets" between adjacent panels. Other causes are heavy vehicles, improper installation, and the heaving or consolidation of soils beneath sidewalks due to groundwater or leaking yard drain lines which lead to differential settlement; however, tree roots are the highest contributor to sidewalk damage throughout the City.
Depending on the nature and severity of the damage, different repair methods are employed. Because the City's policy is to protect trees, major emphasis is placed on maintaining sidewalks in ways that, to the largest extent possible, do no harm to the trees. This often includes root pruning under the direction of a certified arborist to preserve the tree root structure, protect the tree itself, and prolong the life expectancy of the replaced walking surface; tree removal is a last resort.
Maintenance strategies that are routinely employed include:
- Mechanical grinding of offsets that are between 1/2 and 1 inch
- The use of asphalt to "wedge" offsets greater than 1 inch
- Removing concrete panels and replacing them with either asphalt or more concrete, as appropriate, to reestablish the walking surface.
Because of the extensive sidewalk network that the City is responsible for, limited funding, and the continued degradation of this infrastructure, a systematic approach to prioritizing repairs is imperative. During the development of the City's Active Transportation Plan (ATP) in 2009, an analysis and characterization was made of likely pedestrian traffic generators. Schools, transit routes, parks and commercial areas were deemed to be those facilities most likely to experience high pedestrian use. Walking facilities are prioritized in relation to their proximity to destinations; facilities near schools for example, receive a higher relative priority if 1/8 mile or closer (1.25 ATP rating) than those between 1/4 mile and 1/8 mile (1.00 ATP rating).
What to Expect:
• There may be inconvenience associated with driving through the work zone.
• Traffic control and flagging operations will be in effect.
• No-parking signs will be posted at least 24 hours in advance of any parking restrictions.
• Open trenches will be backfilled and/or covered at the end of each work day.
• Emergency vehicle access will be maintained throughout the construction process.
Caring for your infrastructure to keep Kirkland healthy, safe and vibrant.