West Northern Lights Boulevard – Sound Barrier Improvements August 16, 2006 Meeting Purpose: A Forum to Share and Gather Information The Municipality of Anchorage Project Management and Engineering Dept. and CRW Engineering Group, LLC

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 2 Introduction Rebecca Campbell, CRW Engineering Steve Gillette, PM&E

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 3 Study Area West Northern Lights Boulevard – Forest Park Drive to Arlington Drive Overview

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 4 Study Results One 24 hour monitor was set at 2050 Churchill Drive (Ldn) Numerous Spot Measurements were taken along the study area. (LEQ) The Equivalent Level (LEQ)- represents the average noise level for an entire hour The Day-Night Level (Ldn) – 24 hour weighted noise average Noise Study

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 5 Study Results 24 Hour average (Ldn) at 2050 Churchill Drive was 78 decibels (dBA) The standard noise criteria for residential developments are: – Ldn 60 dBAnormally acceptable – Ldn 65 dBAconditionally acceptable – Ldn 70 dBAnormally unacceptable – Ldn 75 dBAunacceptable Noise Study

6 Noise Study Results Peak Hour LEQ

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 7 Sound Barrier Goals Reduce sound levels by 10 decibels Provide a cost effective solution that will benefit the maximum number of residences Maintain the aesthetic properties of Northern Lights Boulevard Maintain the aesthetic qualities of the residences Noise Barrier Options

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 8 Noise Levels Location and Height Barrier Material Utility Impacts ROW Impacts Construction Access Cost Design Factors Noise Barrier Options

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 9 Location and Height Noise Barrier Options Location – Located where the barrier will provide maximum noise reduction – In cut sections, the barrier is most effective at the top of the cut slope – Safety must be considered Height – High enough to block the line of sight of traffic

10 Preferred Location for Maximum Noise Reduction

11 Section A-A

12 Section B-B

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 13 Barrier Material Noise Barrier Options Earthen Berm Wooden Wall Masonry Wall Synthetic Wall

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 14 Noise Barrier Material Wooden Barrier Wooden Barrier - New Seward Highway North of DeArmoun Wooden Barrier - Glenn Highway East of Bragaw Street

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 15 Synthetic Wall Noise Barrier Material C Street North of DimondMuldoon Road at James Drive

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 16 Noise Barrier Costs MaterialCost per foot 1 Total Cost 2 Wooden$380$465,000 Masonry$550$660,000 Synthetic$900$1,080,000 1 Estimated Total Length of Wall Required = 1,200 feet 2 Available budget is $150,000

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 17 Project Schedule Noise Data Collection (April 2006) Design Study (July-August 2006) Public Meeting (August 2006) Design (August – November 2006) Additional Funds Required (April 2007) Bidding (May 2007) Construction (July 2007) Summary

August 16, 2006 West Northern Lights Blvd. Sound Barrier Improvements 18 Contact Information Key Personnel – Rebecca Campbell, PE – CRW Project Engineer Phone Steve Gillette, PE – MOA Project Manager Phone THANK YOU!