Dam struggles in Hillsboro
Hillsboro has a dam problem the Scoggins Dam that creates Henry Hagg Lake, to be exact.
Hillsboro currently gets most of its water from Hagg Lake. But growing demand is projected to surpass that supply by around 2030 or so. Earthquake concerns have postponed plans to raise the dam to supply the additional water. So city officials are looking for a secondary source. The frontrunner is the Willamette River, where Wilsonville and Sherwood already get their water.
"One of our top priorities is always to be able to provide a dependable supply of safe drinking water to residents, businesses and industries at an affordable rate," Hillsboro Mayor Jerry Willey said at last week's State of the City address.
But the city officials are also counting on Clean Water Services the regional sewer and stormwater management agency to find more water over the next 15 years. CWS currently discharges Hillsboros treated sewer water into the Tualatin River. It increases the flow in summer months with water from Hagg Lake to meet environmental requirements. If Hillsboro uses more water, CWS must add even more water to the Tualatin in the summer. The same is true for other cities in most of the county.
CWS is currently planning on getting the additional water by raising Scoggins Dam just for itself a smaller version of the project Hillsboro has decided it cannot wait for. CWS officials say their project must be competed by around 2025 or so to meet the growing demands of Hillsboro and the other water districts in Washington County.
It really does need to be coordinated," says Washington County Commission Chair Andy Duyck. The commission is also the board for CWS.
But CWS cannot currently say for certain when the project will be completed. Scoggins Dam is owned by the U.S. Bureau of Reclamation. It is responsible for improving the structural integrity of the dam to have a better chance of surviving a future earthquake. Only after that can the height be increased to provide CWS the additional water it needs.
And no plan for strengthening the dam has been approved so far. The current proposal calls for extending the front of the dam an additional 300 feet or so with dirt and other materials. It would cost between $330 million and $400 million. But reclamation officials say other, less costly options must be studied before making a final decision and no schedule has yet been set for that.
"This is a very long process. There's not going to be a quick, overnight fix. We need to make sure the government's money is spent wisely," says Chris Regilski, the bureau's Northwest Regional Dam Safety Coordinator.
But even when the final plan is approved, Congress will have to be persuaded to fund it. Oregon First District Congresswoman Suzanne Bonamici says this could prove challenging because the earmarks that used to fund such regional projects have been eliminated. She promises to fight for the project, however.
"It's really critical. You have to have water for growth. Look at companies like Intel, which need to expand," Bonamici said when she visted the district last week.
No specific plan
The delay concerns Duyck. He worries an earthquake could damage the dam before it is strengthened or even after it is strengthened, depending on the magnitude. If that happens, Hillsboro might not be able to meet all of its water needs including residents, businesses and big industrial customers like Intel that are driving the states economy.
So Duyck has begun talking informally with other elected officials in the county about contingency plans. One would have CWS partner with Hillsboro on the water supply project, perhaps paying to oversize the supply line from the Willamette River. That would allow even more water to be pumped to Hillsboro if the citys supply from Hagg Lake is temporarily reduced or interupted.
In exchange, Hillsboro would allow CWS to use water it owns in Barney Reservoir, another though much smaller current source of city water. Duyck reasons that CWS could use that water to increase the flow in the Tualatin River in summer months until Scoggins Dam is repaired.
At this point, Duyck does not have even a preliminary cost estimate for such a partnership. The Utilities Commission that plans Hillsboros water supply system is not expected to officially designate the mid-Willamette River as its preferred alternative until its Feb. 12 meeting. Only then will it begin negotiating with potential partners.
"I don't have a specific plan, but we're willing to talk about it with our potential partners," says Duyck.
But Duycks concern underlines the unease among some regional elected official about the slow pace of the federal decision-making process on the Scoggins Dam project.
Built in 1975
Scoggins Dam was built in 1975 by the U.S. Bureau of Reclamation, which still owns and operates it. The earthen dam is 151 feet high, 2,700 feet long and contains four million cubic yards of materials. The upstream side of the dam is lined with rock riprap for protection against erosion. The downstream side is faced with topsoil and planted with grass.
The dam blocks Scoggins Creek, which drains a portion of the eastern side of the Northern Oregon Coast Range. It creates Henry Hagg Lake, which can hold up to 59,910 acre-feet. It is located approximately five miles southwest of Forest Grove.
A number of different entities own the water in the lake. Half is committed to the Tualatin Valley Irrigation District. One-fourth is committed to Clean Water Services. The remaining fourth is divided between Hillsboro, Beaverton and Forest Grove.
Beginning in the early 2000s, CWS began leading a project to find additional water for all the jurisdictions to meet projected growth. The first choice was raising the height of Scoggins Dam. Raising it 25 feet or 40 feet were both considered. But in 2008, the U.S. Bureau of Reclamation released a study that found the dam sat on an earthquake fault. The agency predicted that a strong enough quake could seriously damage or even destroy it.
That means the dam must be strengthened before it can be raised. The U.S. Bureau of Reclamation is responsible for such work and must pay 85 percent of the cost, with the water users contributing the remaining 15 percent. But assessing the dam, devising a work plan and securing the federal funds is a lengthy process.
The potential delay prompted Hillsboro to launch its own water supply project, which is moving towards choosing the mid-Willamette River. The cost of the project is currently estimated at $870 million in 2012 dollars. Hillsboros share is estimated at $370 million. That includes $8 million to cover the citys costs of the most expensive estimate to strengthen Scoggins Dam. If all goes well, construction could be completed by 2026.
CWS is still working with the reclamation bureau on plans to strengthen the dam. After that work is complete, CWS intends to pay to raise the dam 12 feet to create the additional water needed to increase the flow in the Tualatin River to meet the projected growing water use in Hillsboro and the much of the rest of the county.
It is unclear what CWS will do if the work cannot be completed in time. Staff have discussed options ranging from using treated waste water for irrigation and encouraging large users, like Intel, to recycle more of their own water. They do not know what that would cost or whether it would be sufficient, however.
In the meantime, Regilski will only say it is "conceivable" that CWS will meet its goal of raising the dam 12 feet by 2025.
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