Mercer Island residents already know that single occupancy vehicles may eventually lose access to the center roadway of Interstate 90 for high capacity transit such as light rail. Residents have also been told that to make up for that loss, SOVs will have access to the new carpool lanes established on the outer roadways.

According to a new access plan from the Washington State Department of Transportation, however, DOT officials no longer believe the latter will be necessary.

In a recent letter mailed to the local cities and organizations involved in the I-90 Memorandum of Agreement from 1976, the DOT stated it didn’t see why single occupancy vehicles heading to and from the Island should continue having access to the new R-8A HOV lanes.

The letter, titled “Access Plan for Mercer Island” and dated Sept. 29, 2006, reads, “WSDOT currently does not believe that a period of operation of the outer roadway HOV lanes continuing their availability at no cost for Mercer Island single occupancy vehicles will be consistent with equitable and efficient highway operations.”

In the meantime, the city is asking Sound Transit and WSDOT to reconsider and preserve Islanders’ access to any HOV lanes on I-90 as long as they exist. City Council members mailed a reply to WSDOT Secretary Douglas MacDonald expressing their disagreement with the statement.

“Your definition of equity does not take into account Mercer Island’s existing and current access,” reads the letter. “Another way to consider this issue is that when the center roadway is converted to high capacity transit, Mercer Island will be adversely impacted differently than all other users of the I-90 corridor.”

The letter from WSDOT states that current bus, vanpool and carpool services — as well as possible future additions of more buses and high capacity transit are enough to fulfill the agreement.

“The level of service from the strong vanpool program in King County, along with transit services, suggests there is now excellent opportunity for Mercer Island residents to make choices to use mass transit for personal travel,” the document reads. “Metro’s proposed “Transit Now” program will add frequencies to existing services with an expected gain in ridership of 18 to 20 percent. Sound Transit projections for ridership at the Mercer Island light rail stop indicate 1,500 people a day will ride light rail from a trip origin on Mercer Island.”

According to Judy Ginger, WSDOT’s public transportation and rail program director, all these numbers are indicative of the changes to come for the region’s roadways.

“There are going to be changes happening as Sound Transit moves into High Capacity Transit in the center roadway,” Giniger said. “This access plan talks about the changes that are going to be happening both on the outer and center roadways of I-90 due to the growing congestion from regional population and job growth.”

“(The letter) is saying that we don’t think that continuing to have SOVs in HOV lanes would be consistent with the proviso of the access plan,” Giniger said. “I-90 is a critical part of the regional transportation system and we need to make sure there’s access for all users as congestion rises.”

Lisa Belden O’Meara, an Island resident concerned with the future of I-90, said the document shows that the City Council forfeited Islander’s SOV access to the HOV lanes when it signed the 2004 amendment to the Memorandum of Agreement.

The 2004 amendment states, “To the extent of any loss of mobility to and from Mercer Island based on the outcome of studies, additional transit facilities and services such as additional bus service, parking available for Mercer Island residents, and other measures shall be identified and satisfactorily addressed by the commission, in consultation with the affected jurisdictions.”

City Manager Rich Conrad, in response to the access plan, said the city wants SOV access to the HOV lanes as long as they are free.

“We want a number of things, but most importantly, we want acknowledgment that from the day Sound Transit displaces traffic out of the center lanes to the day the DOT decides to operate the R-8A lanes as HOT lanes, we want our SOV traffic to have access. The new I-90 HOV lanes are eventually going to become HOT lanes and what we’re saying is, ‘The day those become HOT lanes we’ll pay just like everybody else. But before that, while you’re still operating them as HOV lanes, we want access to those lanes just like we had access to the center lanes for the last 30 years,’” Conrad said.