Water rupture shines light on aging infrastructure

Estimated 40 million gallons tapped from reservoir before fix

By James Robinson
Posted 8/28/24

A cracked coupling discovered in the city’s water supply line Aug. 14 leaked more than half a million gallons per day, drew down City Lake Reservoir and underscored the many challenges of …

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Water rupture shines light on aging infrastructure

Estimated 40 million gallons tapped from reservoir before fix

Posted

A cracked coupling discovered in the city’s water supply line Aug. 14 leaked more than half a million gallons per day, drew down City Lake Reservoir and underscored the many challenges of maintaining a city water supply — aging infrastructure in remote and hard-to-access terrain, ongoing maintenance costs, millions required for capital improvements, and environmental change.

City officials issued a mandatory water conservation notice the same day, and by the time crew had repaired the line an estimated 40 million gallons had been drawn from City Lake Reservoir. As part of the conservation notice, the city advised customers to take certain steps, including “reducing outdoor water use for irrigation, taking shorter showers, operating dish and clothes washers only when full, and fixing leaky faucets and/or toilets.”

The city said that soil had eroded near the transmission line in Snow Creek and that it was notifying property owners in the affected area, along with regional and state agencies.

“The pipe was in a hard-to-get-to location,” explained Steve King, the city’s public works director, which made it difficult to discover and contain.   

Now that the repair is complete and the water transmission line again functional, additional assessment for soil and pipeline stability near the leak will be addressed as a followup for the long-term stability of the system.

The culprit was a cracked fitting in the upper waterworks in a steep area. “We estimate that the leak at the time of discovery might have been flowing about 400 gallons per minute,” or 576,000 gallons per day. “There was no way to measure, so this is a visual assessment and estimate,” King said. 

During the summer, absent any emergencies, the city uses approximately 2 million gallons per day; the mill uses approximately 11 million gallons per day.

The reservoir can provide water for a minimum of five days under normal operations. The 40-million-gallon estimate is based on average usage of 12 million gallons per day over a little more than three days, King said.

In managing the leak, the City and Port Townsend Paper Mill both implemented water conservation plans as a precautionary measure to extend the amount of time the reservoir could provide water.

 

Long history

The waterworks, officially known as the Olympic Gravity Water System (OGWS), dates back to the early 20th century.

The OGWS originating from Snow Creek began operation in 1905, but by the mid-1920s, the infrastructure was decaying and having difficulty supporting Port Townsend’s water needs. Community leaders at the time understood that the city’s future hinged upon both a secure water source and industry, and they worked to bring the Crown Zellerbach paper mill to the city. Records show they saw the mill’s arrival as a way to revive the city’s economy and renovate the ailing water system.

In 1927, the paper company constructed the mill. In 1928, the city and the mill built a 29-mile pipeline from the Big Quilcene River watershed to Port Townsend. This water system replaced the failing Snow Creek system. Together, and over decades, the city and the mill replaced the original wood-stave pipe, installed the Little Quilcene Diversion, constructed Lords Lake Reservoir, rehabilitated the Big Quilcene Diversion, and upgraded the City Lake outlet system.

Today, the OGWS sends raw water to the mill for industrial purposes and to the city’s water treatment plant for domestic use. The OGWS provides an average daily flow of 12 million gallons. The maximum daily flow is about 16 million gallons.

Since the pipeline’s construction, the City of Port Townsend has maintained ownership of the OGWS facilities and the water rights, but leased the operation and maintenance of the source water collection and transmission system to the mill. That relationship continues today.

In addition to lease payments, the mill and its various owners — currently Atlas Holdings, LLC — have been responsible for operating the OGWS. Since 1928, the City and the mill have been engaged in a public-private partnership. The most recent operating agreement was signed in December 2021.

“Pipeline failure is inevitable but rarely predictable — which is why it’s critically important to everyone in our community and our future that we negotiated this agreement to provide the resources to do so,” said City Manager John Mauro. He noted the 2021 agreement was “the first time since 1956 there had been any substantive change to how we collaborate with the Mill to operate and repair the water line.”

According to the agreement, “An estimated $161 million in current value infrastructure and other capital assets will need to be refurbished or replaced within the next 40 years, which includes setting aside funds beginning in 2037 to be held in reserve to implement a 125-year replacement schedule for the transmission pipeline installed between 1952 and 1972. This capital improvement program estimates an investment of $64 million in the next 20 years.” For the near term, the capital improvement plan calls for Lords Lake dam improvements in 2025 and replacement of the 1928 pipeline in 2028.

The city plan uses a sinking fund approach to minimize public and private debt. A sinking fund is a fund that holds money set aside or saved to pay off a debt or bond. A company that issues debt will need to pay that debt off in the future, and the sinking fund helps to minimize a large outlay of revenue. A sinking fund is established so the company can contribute to the fund in the years leading up to the debt’s maturity.

“The greatest challenge to the water line in the coming 20 years is likely the scale of investment and the uncertainty of pipeline failure,” Mauro said, adding the pipeline replacement value to be about $120 million “or more.”

Mauro noted that the 2021 agreement also “means that the City team is on point for repair,” when it was previously the mill. “[T]he recent pipe failure was a good and successful test of how we deploy resources and coordinate as the lead,” he said. “Indeed, there are other unknowns and challenges like climate impacts and geological/earthquake hazards to think about, but this can now all be done in the context of this agreement.”

 

Climate change

According to city documents, statewide average spring snowpack is projected to decline 38 to 46% by 2050 and 56 to 70% by the 2080s under low and moderate greenhouse gas scenarios. Reductions of up to 80% are expected under the high emissions scenario. Warmer winters, less snow and more winter precipitation falling as rain are projected to shift the timing of peak spring streamflow to earlier in the year, increasing the risk of wintertime flooding and decreasing summer stream flows. Lower flows in the late summer and early fall will increase reliance on stored water along with other conservation measures in order to meet industrial demand.

The greatest risk related to climate change is a decrease in summer and fall flows in the Big and Little Quilcene rivers. In 2015, low snowpack forced curtailment of a portion of paper mill operations and Lords Lake was drawn down to a point where the necessary flow rate could not be maintained. With climate change, environmental managers expect years like 2015 to increase in frequency. As a result, the most effective strategy, according to the city, is to increase storage capacity in order to capture water during high runoff periods and store it until needed during dry periods of the year. The city’s capital improvement plan includes a plan to increase the storage capacity of the Lords Lake Reservoir by raising the east and north dams.

While there are challenges ahead, environmental managers describe the water quality from the Quilcene Rivers as “exceptional” and, until 2017, it was one of the few permitted unfiltered surface water supplies.

Mauro said the 2021 agreement lays the framework for different things that could happen. For instance, if there is a major drought in the region, the agreement requires conservation by both city water customers and the Mill, “with priority given to human consumption.”

Mauro said he was less concerned about not enough water supply, given those protections, than he was about potential breaks or emergency repairs, “especially in remote areas like the one we just repaired.”

Operation of the OGWS requires a special permit from the US Forest Service for the diversion facilities on the Big Quilcene River, Little Quilcene River, and portions of the transmission pipeline that are located on Forest Service property.

The permit mandates that the city maintain certain in-stream flows. The city’s three U.S. Forest Service special use permits expire in 2029. The 2009 renewal process cost approximately $400,000 for various studies and reviews.