This 2019 WSDOT report analyzes noise barriers along the SR509 Phase 1 highway alignment near the Sea-Tac area, evaluating whether proposed sound walls meet feasibility and cost-reasonableness standards. Wall 3 was rejected because it could not achieve the required 5 dB noise reduction for nearby residents. Wall 4 met the technical noise-reduction threshold but was ultimately rejected because its estimated cost of $111,478 exceeded the allowable budget of $72,254.

Notes

This document summarizes noise barrier analysis for the WSDOT SR509 Phase 1 alignment, evaluating Walls 3 and 4 against feasibility and reasonableness criteria. Wall 3 failed feasibility criteria as the barrier could not achieve the required 5 dB insertion loss. Wall 4 passed feasibility criteria but failed reasonableness criteria because the wall cost ($111,478) exceeded the allowance ($72,254).

Sidebar On/Off

As the source for federal transportation grants, the Puget Sound Regional Council was charged with developing a system to meet the growing need for commercial aviation. When the search for a second airport failed, they authorized the Port of Seattle to build the Third Runway, with a mandate to develop a noise abatement and mitigation program. In their effort to stop the Third Runway, the ACC argued over every detail of the Port's efforts--including property buyouts and sound insulation. The dispute was meant to be settled by a three member Expert Arbitration Panel. This is their final report. It finds 2-1, that the Port's program was insufficient in several respects. Despite that, funding for the Third Runway was approved by the PSRC, and the 'Port Package' program, proceeded largely unchanged. Expert Arbitration Panel's final decision finding that the Port of Seattle had not shown sufficient reduction in real on-the-ground noise impacts to satisfy noise reduction conditions required for approval of a third runway at Sea-Tac International Airport. The majority decision concluded the Port's noise abatement programs were insufficient despite being impressive in scope.

continue...

V V

Notes

Message