Developers for the $1.4 billion Washington State Convention Center expansion are continuing their march through a myriad of reviews with a trip to the Seattle Design Commission this week.

The series of meetings, which are open to public comment and could span most of the year, were triggered when the Pine Street Group developers requested permission to remove portions of three alleys and two streets in the project area — Metro’s soon to be defunct Convention Place Station. In exchange for taking over the streets and alleys, City policy requires the project include improvements to the surrounding area.

Sorting out what those public benefits could be will be a key part of the conversation that happens in the coming months, starting with Thursday morning’s Design Commission meeting at City Hall.

The Design Commission process plays out in two stages. First, the WSCC will go through three “urban design merit” meetings to present their proposed street vacations and show how the design of the project could improve the surrounding right-of-ways. For instance, commissioners may look for the inclusion of street level commercial space to ward off pedestrian un-friendly walls.

In the second phase, the commission considers added public benefits. Design Commission director Michael Jenkins said commissioners typically look for long-term community benefits beyond the scope of the project itself, like enhanced sidewalks, street furniture, and public open spaces.

Some are hoping a much more ambitious idea makes its way into the discussion: Building a new lid I-5 for new housing or public space. Leading the Lid I-5 campaign is the Pike/Pine Urban Neighborhood Council, whose members are hoping the WSCC will fund a crucial feasibility study to establish real lid proposals.

“The commission always wants to see something feasible and tangible,” Jenkins said.

Pine Street principal Matt Griffin has said in the past that a lid project was beyond the purview of the WSCC. However, PPUNC is also exploring the idea of having developers extend the Plymouth Pillars Park off-leash area to cover up a smaller corner of the I-5 canyon. PPUNC chair John Feit has been making the rounds to local design offices in order to recruit architects to create a fresh stack of drawings for the project.

The public benefits phase isn’t expected to start until this summer.

After the Design Commission votes, the final street vacation must be approved by City Council — a vote likely to happen early next year. It’s a crucial step for developers who need the green light from Council before obtaining their master use permit.

Developers have requested the City remove a small section of Terry Ave between Howell and Olive and two alleys in the same block. Plans also call for an 8-foot deep “subterranean vacation” of Olive Way between Boren and 9th Ave. In addition to clearing the block for building above ground, the vacations would also allow for a 150,000-foot exhibition hall below street level.

The street vacations are also important for developers moving ahead on two nearby co-development sites, which could include a 28-story apartment building and 16-story office building with street-level commercial space.

The street and alley vacations are significant, both in what the WSCC gains and what the City gives up, meaning the required benefits must be equally as important, according to City policy:

It is the obligation of the Petitioner to demonstrate that the public benefit proposed be proportional to the benefits gained by the Petitioner and to the scale and impacts of the project. The Petitioner shall provide information regarding the increase in the development potential from the vacation and the assessed value of the adjacent property. In addition, the Petitioner shall provide objective information about the public benefit proposal such as budget information, dimensions or other factual information. A significant public benefit must be provided by major projects, that is those that are large in scale, require a large amount of public right-of-way, have identified impacts or those where the vacation contributes to a significant increase in the scale of the project.

The WSCC addition will be built on land along the north side of Pine just across I-5 from Capitol Hill where King County Metro’s soon to be defunct Convention Place Station is located today. Plans are currently in the works to phase buses out of the existing transit tunnel in order to vacate the space. In November, WSCC reached a deal with the County to buy 4 acres in downtown for $147 million.

Due to its size and complexity in the middle of downtown Seattle, the expansion project also qualifies for a unique process called Planned Community Development. Following an public open house on the PCD, the former director of the City’s planning department identified five public benefit priorities in a memo to developers, including:

Affordable housing that is rent restricted for 50 years for people earning less than 60% of median income, likely to be included at the residential co-development site at 920 Olive Way.

A public plaza at 920 Olive Way or some other type of open space.

Pedestrian improvements around the site.

Integration of public transit into the site, which may include building bus stops or providing real-time transit information.

Meanwhile, a team comprised of various City agencies is meeting regularly with developers to assess impacts the project will have on a wide range of issues, including utilities and traffic.

The Seattle Design Commission meets Thursday, February 4, 2016, 9–11:30 AM, Seattle City Hall, Bertha Knight Landes Reception Room Lobby.

WSCC Proposed Street Vacations