Background
Why is the project needed?
Many residents are concerned with noise in our heavily traveled urban areas. People want solutions that will reduce traffic noise in their neighborhoods. The Washington State Department of Transportation (WSDOT) identified highway traffic noise along I-5, between 5th Avenue NE and NE 92nd Street, as a high priority for noise mitigation.
WSDOT identified this as a priority because when WSDOT built I-5 in the 1960s, noise was less of a concern, largely because there was less traffic. Since then, noise levels increased significantly as traffic grew.
What is the project?
WSDOT is evaluating one noise wall on the east side of I-5 (Stage 2) in this area. This proposed noise wall on the east side of I-5 includes two segments: Wall 1-North, between NE 92nd Street and NE 85th Street, and Wall 1-South, between NE 85th Street and NE 80th Street. WSDOT is also building three noise walls on the west side of I-5 (Stage 1) between 5th Avenue NE and NE 92nd Street.
What is the project timeline?
Stage 1:
- 2005-2007: Complete planning phase.
- 2007-2008: Complete noise wall designs and community polling process.
- 2008-2009: Construction of west side noise walls. Construction of Stage 1 is anticipated to begin in early summer 2008 and will last approximately 10-12 months. The contractor will determine the order in which to construct the three different noise walls.
Stage 2:
- 2005-2007: Planning phase. With support from legislators and the Maple Leaf community in early 2007, WSDOT postponed the design and construction of the proposed noise wall on the east side of I-5.
- 2008-2009: Design east side noise wall and conduct community poll with property owners.
- 2009-2010: With community support, construction of east side noise wall could begin in summer/fall 2009.
Which neighborhoods will be affected by the project?
Neighborhoods affected by this project include Maple Leaf, Licton Springs, and north Green Lake.
What is the project budget?
WSDOT received $14.7 million in funding from the legislature as part of the 2005 Gas Tax to design to build up to four noise walls in the area between 5th Ave NE and NE 92nd Street. This money will be used to design and construct three noise walls on the west side of I-5 (Stage 1) and one noise wall on the east side of I-5 (Stage 2).
Why was the design and construction of the noise wall on the east side of I-5 postponed?
Sound Transit plans to build a light rail line in the same vicinity as the proposed noise wall on the east side of I-5. In 2006, WSDOT held a meeting with neighbors to discuss the potential schedule and location conflicts. WSDOT was concerned that the noise wall would need to be demolished and rebuilt after only a few years to accommodate Sound Transit’s North Link light rail construction. With support from legislators and the Maple Leaf community in early 2007, we postponed the design and construction of the proposed noise wall in this area, pending the results of a 2007 ballot measure to fund the light rail project.
Since the funding for proposed light rail line was rejected by voters in November 2007, WSDOT is moving forward with the design of the proposed noise wall in the Maple Leaf neighborhood and will continue to monitor Sound Transit’s plans for light rail in this area. In early 2008, we completed preliminary design work, including identifying the location and height of the proposed noise wall, as well as modeling potential noise reduction benefits.
What is a noise wall?
A noise wall is a barrier that can be constructed from a variety of materials. WSDOT typically uses concrete for noise walls. These noise walls vary in height and appearance depending on the location of their installation. For Stage 2 of this project, we are considering using lightweight materials rather than traditional concrete.
How does a noise wall work?
Noise walls reduce highway traffic noise from entering adjacent neighborhoods by reflecting or diffusing the noise. To achieve the maximum noise reduction possible, a noise wall must be tall enough and long enough to block the view of a highway from your home.
What types of noise walls is WSDOT considering for Stage 2?
WSDOT is considering using some newly available non-concrete noise wall products (pdf 120 kb) rather than typical concrete for this noise wall. These non-concrete products are commercially available, lightweight, and could potentially be disassembled and reused elsewhere if Sound Transit’s light rail project moves ahead in this area in the future. If the light rail project does not move forward, these materials are durable and would be permanent.
The use of a non-concrete type of noise wall would be new and innovative for the state. We plan to monitor the condition (wear and tear) of the noise wall over time and evaluate the maintenance requirements and qualities.
How does WSDOT decide where to build noise walls?
WSDOT considers constructing noise walls for two scenarios:
- Scenario 1: WSDOT considers constructing noise walls in neighborhoods that will experience an increase in traffic noise after the completion of a state highway project, such as a new road widening project. Design and construction of these walls are added to the scope and budget of the highway project to reduce the overall effect of increased traffic noise on the surrounding community.
- Scenario 2: Noise walls are also considered for neighborhoods that were developed prior to May 14, 1976 that are adjacent to major freeways currently experiencing a high level (66 decibels or higher) of noise. At 66 decibels (dBA), most people find it difficult to have a conversation outside. The qualifying neighborhoods are prioritized statewide to receive traffic noise reduction as funding allows. The I-5 / 5th Avenue NE to NE 92nd Street Noise Wall Project was awarded funds as part of this statewide noise program.
How are neighborhoods ranked on the statewide priority list for noise walls?
Neighborhoods are ranked based on a number of factors including cost of the wall, the level of noise from the freeway reaching their homes, the amount of noise reduction a wall will achieve for surrounding neighbors, and the number of people that will benefit from a wall.
Why are some noisy neighborhoods not on the statewide noise wall priority list?
Only neighborhoods that were developed prior to May 14, 1976 can be considered for placement on the statewide noise wall priority list. This is because federal guidelines intended to provide noise relief for areas that existed before the policy was implemented. When I-5 was originally constructed, the increase in traffic noise was not addressed. Since the completion of I-5, new roadway improvement projects now include evaluation of noise walls or other treatments (as applicable) to reduce the net increase in noise, so these areas are not considered for the noise wall priority list.
How is noise modeled?
WSDOT builds a model of the project area to approximate noise levels. WSDOT then takes field noise measurements to verify the modeled noise levels. The model uses a variety of factors to determine the approximate existing and future noise levels in the project area. These factors include existing traffic noise levels, topography, and the locations of homes relative to the proposed location of a noise wall.
What are the current noise levels in the area?
Using noise samples collected on the west side of I-5, noise levels in this area range from 59 to 81 dBA. Noise levels on the east side of I-5 in this area range from 58 to to 77 dBA. Please download our noise thermometer image (pdf 282 kb) to learn more about varying activities and their approximate noise levels at certain distances.
Has WSDOT considered other methods to reduce noise?
WSDOT has selected quieter pavement test sites to see how quieter pavement performs in the Pacific Northwest's unique driving and climate conditions. WSDOT is studying the test sections of quieter pavement for five years to measure durability, quality and quantity of noise reduction, and how noise suppression abilities perform over time. This information will help policymakers, WSDOT, and others make more informed decisions about incorporating quieter pavement into highway projects in the future. Please visit the Quieter Pavement Web site for more information.
Has WSDOT considered re-paving the section of I-5 in this project area?
WSDOT is looking at methods to replace the pavement in this area, and experiencing some challenges with the existing pavement because it is not very thick and may easily break down when re-paved. For more information about pavement rehabilitation please visit WSDOT's I-5 Reconstruction Projects Web site.
What construction company has WSDOT contracted for Stage 1 of this project?
WSDOT selected Granite Northwest doing business as Wilder Construction Company to construct the three noise walls on the west side of I-5 through a competitive bid process.
What days will there be construction?
The contractor will primarily work Monday through Friday between 7 a.m. – 5 p.m. For any night or weekend work, we will notify residents in the area.
Will lanes or ramps on I-5 be closed?
Lanes and ramps will be closed on an as-needed basis, including at night, during construction to ensure safety of the drivers while crews construct the noise walls. WSDOT will notify the public via variable message signs along I-5 and through the project Web site about the lane closures. This information will be posted in advance to the public once the contractor submits their timeline.
Where will traffic be rerouted when ramps are closed?
From N 85th Street to N 80th Street, traffic will be rerouted to NE 70th Street via Southbound I-5. Traffic traveling eastbound from Corliss Way North to N 80th Street will be rerouted across I-5 and along Banner Way back to N 85th Street. Detour routes will be clearly signed.
How will WSDOT ensure the safety of both drivers and workers?
Workers will wear reflective clothing to provide good visibility to motorists. Flaggers will direct traffic during city street closures. There will be clear and consistent construction signing and traffic-control devices. The public is advised to reduce speed and to be alert when driving through the construction work zone. Safety is everyone's responsibility, Give 'em a BRAKE!
Are there other temporary effects due to construction?
There will be some increased noise, dust, and potentially light due to heavy machinery used to construct the noise walls. Construction crews will use typical practices to best address these effects.
Where will Wilder Construction stage their equipment?
Construction equipment will be set up on the WSDOT right-of-way. Currently, Wilder plans to place their construction trailer near Wall 4 along 2nd Ave in the WSDOT right-of-way.
Will WSDOT remove trees along I-5?
WSDOT’s goal is to retain as many trees and plants currently near the wall location as possible. We altered the design of the Stage 1 noise walls to retain the maximum amount of trees at the community’s request. To accommodate the equipment needed for construction, WSDOT will likely need to remove some trees nearest the proposed noise wall locations. Trees that are on the residential side of the noise wall that have branches overhanging into the WSDOT right-of-way may need to be trimmed to accommodate construction.
When the project is complete, we will re-establish vegetation lost along the roadside during construction. Any new plantings will be consistent with the existing landscaping along this stretch of I-5. We will also provide information to neighbors about what types of landscaping would work well on the neighborhood side of each noise wall.
Will property adjacent to the noise wall locations be affected during construction?
The construction crews will clear (pdf 259 kb) approximately 3 feet on the residential side of the noise wall location within WSDOT right-of-way. Crews will access the construction area from the highway side of the noise wall locations. While we construct Walls 2 and 4, crews will need to remove the chainlink fence behind properties to access the area within WSDOT right-of-way where the noise wall will be located. We will install temporary fencing during construction to replace the chainlink fence.
How will WSDOT keep nearby residents informed of construction activities?
WSDOT will notify the public via fliers, e-mail updates, and project Web site about the construction activities.
Where should I go if I have questions regarding this construction?
- Visit the project Web site: wsdot.wa.gov/Projects/i5/5thAveNEtoNE92ndNoiseWall.
- Send a message to the project team: NWNoiseWalls@wsdot.wa.gov.
- Call the construction information line: 206-819-7230.
How much noise reduction will neighbors experience from a noise wall?
Noise reduction will depend on the height, length, and material of the wall, as well as the distance between each home and the wall. The first row of houses behind a constructed noise wall may experience up to a 50 percent reduction in perceived freeway noise. Adjacent neighbors may experience noticeable reductions in freeway noise up to three rows back from the walls, depending on the topography.
Will a noise wall reduce all noise in my neighborhood?
Noise walls are constructed to reduce freeway noise, which sometimes masks other noises in the neighborhood. Once a wall is constructed, other noises in your neighborhood that are not coming from the freeway may become more noticeable.
Will a noise wall reflect noise over the freeway and into the neighborhood on the opposite side of I-5?
A wall on one side of the freeway is very unlikely to act as a "sound board," reflecting noise to the neighborhoods across the freeway. The I-5 corridor is very wide, and reflected noise would disperse very quickly, making it difficult to hear over the direct noise from I-5. Please visit the Federal Highway Administration’s highway traffic noise Web page for additional information about noise walls and how noise travels.
How will changes to my view be considered?
WSDOT recognizes that the proposed noise wall may block the scenic views that you and your neighbors enjoy. Before designing the noise walls on the west side of I-5 in this area, WSDOT conducts a neighborhood poll to determine if the neighborhood supports constructing the noise walls.
How will the noise walls alter the landscaping near the freeway?
WSDOT will work with the community and the construction team to help minimize effects to trees and other landscaping (pdf 129 kb). To accommodate the equipment needed for construction, WSDOT will likely need to remove some trees nearest the proposed noise wall locations. When the project is completed we will replant to re-establish vegetation lost along the roadside during construction.
What design treatment will be used for Walls 2, 3, and 4?
During summer 2007, WSDOT held a design workshop for property owners near Walls 2, 3, and 4. Neighbors were asked to provide input on the design treatments for the neighborhood side of the noise walls. Based on community preference, we will design the neighborhood side of each wall using the following patterns:
• Wall 2 (pdf 545 kb) - Ashlar stone pattern
• Wall 3 (pdf 616 kb) - Ashlar stone pattern
• Wall 4 (pdf 590 kb) - Dry stack stone pattern
Who is eligible to participate in the community poll?
Property owners who have property behind the proposed noise wall and within 500 feet of the edge of the traveled lane of I-5 are eligible to participate in a community poll. This is because noise walls are designed to reduce noise in neighborhoods close to major highways. Given the characteristics of how noise travels, noise walls are most effective at reducing noise up to 500 feet from the edge of the traveled lane of I-5.
A poll for eligible property owners on the west side of I-5 (Stage 1) was conducted in June 2007. A poll for eligible property owners on the east side of I-5 (Stage 2) is being conducted in July 2008.
How does the community poll work?
WSDOT sends ballots and noise wall specific information to eligible property owners. The packets include information about the characteristics of the proposed noise wall closest to the property owner and a ballot. For the July 2008 community poll, ballots must be postmarked by July 17, 2008 to be considered. Only completed ballots arecounted - if property owners do not return a completed ballot, their preferences will not be included in the poll.
How are the ballots counted?
There is only one polling ballot per property. Property owners with a property closest to the noise wall (with a direct line of sight to the wall) will have their ballots counted as 1.5 votes per property. All other properties within 500 feet of the edge of the traveled lane of I-5 will have their ballots counted as 1.0 vote per property. When all ballots have been recorded, WSDOT will evaluate the results to gauge community support.
Why are the ballots weighted?
The ballots are weighted to reflect how different properties will benefit and be affected by the proximity to the proposed noise wall location. Property owners with a property closest to the wall (with a direct line of sight to the wall) will experience the most benefit from the noise wall and may experience other effects during construction and once the wall is completed. Examples of these potential effects include:
- Short-term construction effects (e.g., increased noise, artificial lighting, dust).
- Alterations, removal, or replacement of the property owner’s fence.
- Changes to outdoor use of property (e.g., planting areas, gardens, sitting areas).
- Unauthorized use of the space between the noise wall and chainlink fence.
- Increased shading and/or reduced natural light.
- Changes to landscaping near the proposed wall location, to accommodate construction.
How will WSDOT make the final decision regarding the noise wall?
The community poll is one of many sources of public input that WSDOT receives before continuing with the design and construction of noise walls. Other sources include correspondence with individual property owners, local community organizations, elected officials, and input collected from community meetings.
What are the implications of a “No” vote?
There is a poll being conducted for wall segments, Wall 1-North and Wall 1-South. This means that either of the segments could be built, or either of them might not be, based on community support. If the community indicates that they do not support a noise wall, WSDOT will not build this segment of the noise wall.
Due to the unique circumstances of Sound Transit’s proposed light rail project in this area, the Maple Leaf neighborhood would stay on the statewide priority list. However, the funding allocated from the 2005 Gas Tax to build this noise wall will be returned to the state for use in other projects. If the community decides they do want a noise wall in the future, they will need to pursue additional funding to design and construct the noise wall.