Published 3:55 pm Monday, June 2, 2025
NEHALEM, Ore. — Leo Kuntz coined the term for and patented the “muted tidal regulator,” a device attached to tidegates to foster fish habitat and preserve farmland.
Tidegates are essential — and a problem. Tidegates close as the tide comes in. As the tide recedes, the gates reopen to let the water drain. They make farming possible in fertile deltas, but also block fish and limit fish habitat.
A muted tidal regulator controls the inland water level, but also maximizes the time the gate stays open and slows — or “mutes” — the speed of the water. Both are important for fish passage.
Muted tidal regulators can be found up and down the West Coast, balancing agriculture and salmon recovery. “I try to stay in the middle,” Kuntz said. “In compatible restoration, both sides give a little.”
Kuntz, 71, patented the muted tidal regulator two decades ago and fabricates them at Nehalem Marine Manufacturing, a business he started 49 years ago to build boats.
A small crew works in a shop accessible up a gravel road on a hill overlooking Kuntz and his wife Mary’s beef cattle ranch.
Muted tidal regulators come in three sizes. Kuntz said he’s lost track of how many he’s made. “I quit counting at 500, years ago,” he said. “They sold themselves.”
A muted tidal regulator works like a float in a refilling toilet. As water flows inland through an open gate, the regulator rises and closes the gate. As the tide goes out, the inland water pressure pushes open the gate.
Jenna Friebel, executive director of Skagit County Drainage and Irrigation Districts Consortium and a hydrologist, has worked with Kuntz on four projects in the northwest Washington delta.
Muted tidal regulators are suitable in places where saltwater intrusion into the system is less of a concern, she said.
“He’s very innovative,” Friebel said of Kuntz. “The quality of his work is top-notch.”
Kuntz grew up on the Northern California coast and his formal education ended in the ninth grade. He recalled making more money at 16 fishing for one weekend than a school teacher made in a year.
“So it got pretty hard to go back to school,” he said.
He’s always worked on the water, or underwater. One job was to repair old tidegates. “The minute I saw the tidegates, I thought, ‘I can build a lot better tidegate than that,’” he said.
The heavy top-hinged iron tidegates Kuntz saw snapped shut and it took a lot of water pressure to reopen them again to let the water out. The gates were closed for too long. And once the gates were forced open, the water shot out too fast.
Kuntz went to work on building a better tidegate. One improvement was making side-hinged gates. Another improvement was replacing iron gates with lighter aluminum gates. “Water pushed it open so much easier,” he said.
The muted tidal regulator introduced a way to control the level of water inland and kept the gate open as long as possible but prevented damage to farms and structures.
“Unfortunately, heretofore there has been no practical way of accomplishing this goal,” according to the patent issued in 2006 by the U.S. Patent Office.
Kuntz recently showed a muted tidal regulator at work at the mouth of a slough off the Nehalem River near the Oregon coast. The gates were open and the water was slowly flowing through, “That’s nirvana,” he said.
