A draft environmental impact statement (EIS) for the second phase of the Energize Eastside project was released on Monday.
The statement was released by Energize Eastside and is being reviewed by Puget Sound Energy (PSE) and marks another step toward creating greater power load capacity in the Eastside power corridor.
Key to the Energize Eastside plan is the creation of a new substation, called the Richards Creek substation, in Bellevue. Some 18 miles of new wire will be installed, stretching from Redmond to Renton and passing through Bellevue and Newcastle and Kirkland.
In particular, the wire would be a 230,000-volt wire that the new substation would convert to usable 115 kV. The project is estimated to cost between $150 million and $300 million, said Diann Strom, spokesperson for PSE.
Strom said the cost, like other capital improvement projects, would be spread out among their 1.1 million customers.
Energize Eastside was proposed after PSE concluded that the system would be strained to meet power needs during peak power use events, especially during hot or cold weather. These problems could begin to crop up as soon as next winter, the EIS said.
If the power systems are overloaded, PSE would be faced with either leaving the power on and risking substantial harm to power infrastructure, or enacting blackouts to reduce the overall burden on the system in a process known as load shedding, the statement said.
“Once equipment is in an overload condition, the options are to let it fail or take it out of service,” the EIS read.
The majority of these outages were predicted to occur between Redmond and Renton in the corridor that Energize Eastside hopes to improve.
The reason for an increasing demand for power stems from a projected population increase of roughly 1.2 percent annually over the next decade and an increase in jobs of 2.1 percent each year. PSE also estimated the demand for peak electrical performance will grow at a rate of 2.4 percent annually.
The top three current land uses being served by the power corridor are residential at 38 percent, vacant land at 16 percent and 11 percent for commercial.
The substation site itself would sit on roughly 8 acres and be situated in an industrial neighborhood.
Roughly two miles of power lines would run from the Sammamish substation in Redmond through the city, with the remaining 16 miles stretching down to Renton.
The installation of the new wires would likely be on existing easements instead of public right-of-way, the EIS said.
Additionally, the wires that would be used will be above-ground as opposed to buried cables.
The EIS said underground lines require larger conductors and are more costly to construct and maintain. Current costs for underground wire, not including the right-of-way costs, were up to $28 million per mile versus only $4 million per mile of above-ground wire.
While the majority of the project can be completed on existing easements on the current power corridor, some portions of the Energize Eastside plan would have to be secured from landowners or other entities, Strom said.
The statement also backs up PSE’s initial estimates of the project scope and need provide the Eastside with reliable power, Strom said.
“We’ve barely begun to read the EIS, but it extremely supports what we’ve been saying all along,” she said.
A final EIS will be released later this year as the project progresses.