October 4, 2018 POWER INFRASTRUCTURE FOR THE COLUMBIA BASIN PROJECT
By Christina Wyatt, Manager of Power Supply & System Planning, Big Bend Electric Cooperative
At the most basic level, electric power in the northwest is generated by the dams on the Columbia and Snake Rivers, along with a few other facilities. This energy is transported by a network of high voltage transmission lines to local substations, then along distribution lines by your local power company to homes, businesses and farms. This is the same infrastructure required for the new pumping plants under consideration for the Odessa Groundwater Replacement Program (OGWRP).
When a new electric service request is received by an electric company, that company evaluates its existing electric system to determine if they are physically able to serve the requested load. The demand of the facility, which represents the largest electrical need at one time, and the location, are the most important pieces of information required for this analysis. Most often, this process is informal and cursory for a small business or home. However, a larger request will be reviewed by the company’s system engineer to determine the ability to provide adequate voltage to the new load. If the existing system is not large enough to support the load, upgrades would be required. These upgrades might consist of larger wires to be installed, the system voltage to be increased, the distribution system to be re-configured, a substation to be constructed and/or transmission work to be completed.
As the OGWRP individual pumping plans are being contemplated, both the required horsepower of the plant and its location are important. Just as important, are the locations and deep-well horsepower which will be eliminated when the surface water is distributed. If retired deep well pumps are on the same electrical circuit as the new pumping plant and represent an equal offset to overall horsepower, fewer upgrades are more likely. Conversely, if the location is far away (electrically) from an existing substation, or requires a very large amount of horsepower, the amount of required upgrades increases. The number of deep well pumps being retired may not represent enough in horsepower to offset the new pumping plant. This may also be due to the location of the deep wells in respect to the location of the pumping plant along the canal.
After the size and location of the pumping plant and the required electric system upgrades are determined, time is necessary to implement the work. Depending on the system upgrades required – distribution or substation/transmission – the planning and construction process could take anywhere from a couple of years to more than eight years. Substation and transmission projects require coordination with Bonneville Power Administration, the state and the county for technical and environmental reviews. Alternatively, if the pumping plant is a gravity system, there are minimal electrical requirements. This type of facility, if located in close proximity to distribution lines, could be connected with less lead time by the electric company.
There are also contractual issues that must be addressed. Some of the generation produced by the Bureau of Reclamation is designated for the use of the irrigation project. This is known as ‘Reserve Power’. Big Bend Electric Cooperative is working with federal agencies and the East Columbia Basin Irrigation District on contract language that insures this preferential treatment.
As we all work together to reduce pumping from the Odessa Aquifer, electrical needs are one more integral part of the big picture that are being factored into OGWRP planning and implementation.