SELAH, Wash. — Conserving water is a long-term proposition, but when irrigation districts can find ways to invest in their systems over time, the payoff for their members can be significant.

Over the past 20 years, the Naches-Selah Irrigation District, or N-SID, in Central Washington has been making steady improvements to its aging infrastructure so it can maximize water efficiency for its 1,874 landowners.

N-SID Manager Justin Harter and his team began implementing their modernization plan in 2006, installing a series of automated gates, replacing and repairing pipes, and lining canals with concrete across their 10,600-acre service area. The result has been an annual savings of 6,200 acre-feet of water over the past two decades.

“We’ve been pretty ambitious since I got here, spending more than $21 million to upgrade our systems and infrastructure,” said Harter, who was tasked with putting the district’s modernization plan into motion when he was hired in late 2004. “It takes time and money to do these types of improvements, especially with a smaller district like ours. But we are really starting to see the benefits of our long-term plan.”

Harter noted that the N-SID — which dates back to 1888 and hadn’t undergone any major improvements since the 1960s — had already begun planning and upgrading their systems before his arrival.

However, the project really started to pick up momentum after the district conducted a feasibility study in 2006.

“That study became the basis for the modernization plan,” he said. “We decided to keep the main canal open because, from the Naches River, the water drops about 46 feet over 15 miles and falls more than 200 feet in our service areas. We were able to take advantage of gravity to improve our water availability and delivery rates.”

In recent years, N-SID lined 4 miles of canals with geomembranes and concrete, enclosed 10 miles of canals with piping, and installed 12 automated gates to control water flows remotely.

The initial gate was installed in 2007, and the district achieved full automation in 2012 with the final six gates. Harter said the canal gates — which control water levels and flow via upstream and downstream sensors — have been a game-changer for his team of seven.

“We are now heavily reliant on automation,” he said. “It has helped us improve service to our landowners, and it has resulted in better safety and control of our systems. Plus, it has saved us millions of dollars.”

Harter explained that, without automation, many additional miles of new pipe would have been needed, costing the district about $5 million, plus maintenance. The automation project, on the other hand, has cost about $1.1 million to date for the equipment, software and structural modifications.

About 80% of the acreage in the N-SID is used to grow tree fruit, and landowners have reaped the rewards of the automation system and infrastructure upgrades implemented over the past two decades, now enjoying a 100% delivery rate.

“We no longer see spills off of the delivery system,” Harter said. “We have been able to move the spills up the canal, which return to the Naches River.”

The next step in the modernization plan will be to replace the 1,800 feet of wood siphons still in use across the district. Harter hopes most of the remaining work will be completed over the next few years.

“We have made good progress, but our work isn’t done yet,” he said.