Is the tunnel proposal environmentally sound?By cmadden | February 10th, 2009 | Category: Featured story |
By Sound News reporter Christina Madden
Mayor Greg Nickels announced the decision for the bored tunnel design that would change Seattle’s waterfront and said, “We reclaim our destiny as a true waterfront city-tearing down an elevated highway and re-connecting Seattle to Elliott Bay.”
This tunnel proposal, selected by the state’s governor, Christine Gregoire, would satisfy the structural needs. But the extent of environmental affects on Puget Sound are still in question. The bored tunnel would replace the structurally unfit Alaskan Way Viaduct.
Proponents of the tunnel say it would create less toxic stormwater runoff into the Sound, a better aquatic habitat and a possible increase in awareness of the environment for those visiting the waterfront.
The four-lane deep bored tunnel would extend from Harrison Street to just north of South Royal Brougham Way. Along with the construction of this tunnel there would be improvements to city streets, the city waterfront, and transit. A new seawall is part of the recommendation as well.
The total cost of the investments for the upgrades is $4.24 billion. The state’s vow to pay $2.82 billion would go towards the bored tunnel between Safeco Field and South Lake Union. Additionally, the state’s fund would restore the land under the current Viaduct to create a four-lane surface street.
Gregoire said the state rejected the proposal for solely constructing the surface street option because it would negatively impact road conditions on Interstate 5. ultimately leading to a worsened environment, increased pollution and carbon emissions.
She also stated in her tunnel proposal that it will “improve the environment by eliminating a lot of toxic water going into Puget Sound.”
This filtering will be done by state of the art storm water treatment facilities said Matt Preedy, the State Department of Transportation’s Deputy Program Director for the Alaskan Way Viaduct. These treatment facilities are not present with the current structure.
People for Puget Sound’s Urban Bays and Toxics Program Manager, Heather Trim, explained how the tunnel will not only improve storm water runoff, but minimize the problem because there is less pavement, leading to less runoff. Although this will help, Trim noted the importance of reducing the number of cars traveling on city streets because they are a huge source for toxic pollutants into the Sound.
Investments in this proposal will add about 17,000 new riders to King County Metro buses, cutting down emissions in the city, according to Gregoire. More Metro riders means fewer drivers will be on the road and thus less stormwater runoff draining into the Sound.
Mike O’Brien, chair of the Cascade Chapter of the Sierra Club, expressed how the tunnel would have an impact on the waterfront. He stressed that by removing the Alaskan Way Viaduct people could “get down to the waterfront and experience.” He is a proponent of the surface transit option, but noted that both options remove air pollution from the wildlife and habitats of local animals. For example, the fish in Puget Sound will have a better habitat with less pollution submerging into their waters.
In a report released by The Alaskan Way Viaduct and Seawall Replacement Program, it states that there would be “opportunities to improve aquatic habitat conditions along the central waterfront.” Habitat panels would be placed on seawalls, making the surface friendlier to live on for aquatic creatures as opposed to a flat surface. Pier 48 would also be removed, creating an area to construct a new beach.
Opening up the waterfront was a major factor when considering proposals for the replacement of the Viaduct. Preedy said “with the Viaduct gone [it] allows opportunity for public use.”
Although an opponent of the tunnel, O’Brien expressed similar approval of accessibility and importance of the waterfront by explaining how people will be able to recreate and hang out where the Viaduct once stood. He went on to say that it can “become the core of the city.” He explained how behavioral changes can lead to environmental changes. By this he meant that more people will begin to live in the area, thus reducing the length of trips for some drivers.
Not all environmentalists are at ease with the bored tunnel plan. Despite a possible decrease in length of trips, O’Brien believes that by creating a tunnel that does not have as many on and off ramps as the current structure, people will make more trips back and forth, thus producing more emissions.
Whether or not there are more trips, Trim stressed that an “elevated freeway has an air quality impact” and that an “underground structure can reduce this.”
A fixture that has been with the city for decades may finally be torn down as a result of not only structural needs, but environmental concerns.