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What is an Environmental Assessment?

An Environmental Assessment (EA) looks at how a project affects its surrounding environment.

In an EA, we look at two things: Completing the project or doing nothing. The “doing nothing” scenario is a No Build Alternative. When we look at how a project may affect the environment, it is compared against the No Build Alternative.

Why was a Supplemental Environmental Assessment (SEA) prepared for this project?

The project has gone through design and alignment changes. About ten years has passed since completion of the previous environmental assessment (EA). This NEPA study is now out of date. This led to a need for a SEA and new technical studies.

The SEA is a supplement to the 2013 Revised Environmental Assessment.

WSDOT began updating the 2013 Revised EA documents in 2020. Changes include:

  • Updating the project name from SR 3 Belfair Bypass to SR 3 Freight Corridor – New Alignment
  • Revising endpoint designs consistent with new traffic data, which suggests the north and south connections would be better served with roundabouts instead of signalized intersections.
  • Shifting the 2013 alignment to:
    • Minimize or avoid impacts to wetlands
    • Eliminate impacts to the ballfield at North Mason High School
    • Eliminate the proposed bridge north of the Alta-Brook neighborhood
    • Reduce property acquisition needs
    • Be compatible with commercial growth along the existing SR 3 corridor, specifically at the north connection
    • Updates due to changes in federal and state environmental regulations, such as protected species and critical areas (under the Endangered Species Act) regulations.
A map of the area with property lines. The map shows the project area along with the land use for each area. Most of the right half of the map is forest land. As it moves towards the middle and left, colors for residential and commercial are shown. Most of the proposed new highway goes through forest land or the edge of residential areas.

Environmental Overview

Anticipated Project Impacts to the Natural and Built Environment

Transportation (PDF 3.7MB)

SR 3 in Belfair has a high volume of traffic during commuter hours.

Without a new highway, traffic will only get worse. Delays will increase, as will travel times. This will affect emergency response times as well. Gaps in traffic will shrink. This will make getting in and out of businesses on the highway harder.

A new highway may reduce congestion by as much as 43 percent. A freight corridor would send through-traffic around Belfair’s core. This would reduce congestion and improve travel times through Belfair.

Public transit would benefit as well. Reduce congestion and delays would make transit schedules more reliable. The bypass would also give regional transit a faster route through the area. A second highway through Belfair would also give emergency responders another choice during emergencies.

As a result, the analysis in the SEA shows no adverse effects to traffic.

Noise (PDF 1.8MB)

A noise study look at noise levels on the SR 3 freight corridor through 2050.

Noise receivers near the new freight corridor would see an increase of 5 to 20 decibels. Other locations, along the current SR 3, would see a decrease in noise. This is because some vehicles will divert onto the new highway.

The study looked at noise level increases for 15 specific nearby properties. Five properties already exceed the standard set by the Federal Highway Administration. Another 10 would see large increases in noise if the project were built.

Noise walls were not recommended for construction this project. The study found walls were feasible, but not reasonable or cost effective. They did not meet WSDOT’s standards for noise abatement.

Air quality (PDF 481KB)

The project would have no adverse effect on local air quality. Moving traffic onto a separate bypass would reduce congestion through Belfair. Reducing congestion would reduce emissions. It would also allow vehicles to drive at moderate speeds during commuter hours. This would also reduce emissions and improve air quality.

Wetlands (PDF 58MB), fish and wildlife (PDF 372KB) and vegetation (PDF 306KB)

This project will pave over existing wetlands, buffers and vegetation. It will add roadways with shoulders and stormwater facilities.

The proposed design would impact one tenth (0.11) of an acre of wetland habitat and 5.44 acres of wetland buffer habitat. 79 acres of vegetated land would be permanently affected. Another four acres of residential land would also be affected.

Building a new roadway through forestland will have some negative impacts on wildlife. It would bring cars to the undisturbed woods. That will increase the risk of crashes involving wildlife.

Adding the bypass may disturb some animal habitats. The new road could move animals currently living there into a neighboring habitat.

WSDOT will take every step possible to minimize these impacts. This may include building retaining walls and steeper slopes away from the highway. Once construction is complete, native vegetation will be reintroduced to the highway roadside.

Water resources (PDF 4.5MB)

Construction could have a temporary effect on nearby water. This includes floodplains and surface and groundwater quality. But we do not expect any direct or indirect long-term effects to water resources.

This project will build 33 acres of new impervious surface. But this surface will receive stormwater treatment and flow control. This will mitigate any effects to the area’s water quality.

Land use (PDF 952KB)

For this project, WSDOT will buy 115 acres of land in about 72 parcels. Property acquired will be converted to a transportation use. A majority of this land is undeveloped forest. The buying of this land is not expected to affect or influence existing or future planned land uses,

All impacts to property from acquisition would be minimized further, where possible, during final design.

No adverse land use impacts are anticipated as a result of the project.

Socioeconomic and environmental justice (PDF 393KB)

As part of this EA, WSDOT looked at the project’s affect on the Environment Justice population. This includes the minority, low-income and limited English proficiency (LEP) population.

The study found that the project will have minor negative impacts. These impacts affect the population as a whole. It concluded there were no disparate impacts for minority, low-income, or LEP populations in the area.

Hazardous materials (PDF 40MB)

For this project, WSDOT does not need to buy any contaminated sites. Contamination may already be present along the proposed route. If found, WSDOT will dispose of any harmful material.

No significant, adverse impacts are expected to result from the proposed project.

Archaeological and historic resources

This project must follow Section 106 of the National Historic Preservation Act (NHPA) of 1966. This is because it needs an SEA.

The proposed project would not have any effect on historic properties. The Washington State Department of Archaeology and Historic Preservation (DAHP) has agreed. It issued a conclusion on November 28, 2023.

Public services and utilities (PDF 703KB)

This project will not have any negative effects to public services or utilities.

This is an undeveloped area with few intersections and few utilities.

There may be temporary affects during construction. Nearby utility costumers may see intermittent interruptions. These should only last a few minutes at a time.

Construction may also increase congestion on SR 3. But in the long run, it will offer faster travel times between Shelton and Bremerton. Emergency services will also have a quicker route through Belfair.

Visual quality (PDF 1.8MB)

Since this project will clear out forest land, the visual quality of the area may be affected. WSDOT will take measures to ensure the visual quality is not impacted in the long-term.

Geology and soils (PDF 353KB)

This project will not have any unavoidable impacts to the soil in the area.

There is potential for increased erosion and effects to nearby shallow water wells.

WSDOT will look closer at this during the design phase. During construction, WSDOT will work to reduce erosion.

Summary of project benefits

  • Lower traffic volumes through the community of Belfair. This project would reduce congestion and improve safety through Belfair. It would also provide another route during highway closures.
  • Beneficial impacts to transit operations. Reduced congestion and delay would allow for efficient transit operations and the bypass would provide alternate faster regional transit routes.
  • Reduced noise in some locations along the existing SR 3 alignment. This is because vehicles will divert to the new freight corridor.
  • A slight decrease in air quality pollution. This is due to fewer vehicle miles traveled if the project is built. It would be slightly higher if the project were not built.
  • No direct stormwater discharges to surface waters.
  • Emergency service providers (police, fire, emergency medical, etc.) would experience faster and safer response times. Public transit would be able to offer faster travel times between Shelton and Bremerton.
  • Improved travel time and operating speeds for through-traffic on the Freight Corridor. This is expected to benefit the economic growth in the region.