FAIRFIELD — The restoration of more than 600 acres back to historical tidal and seasonal wetlands in Solano County is the first project to receive grant funding from the voter-approved Measure AA.

A Montezuma Wetlands Restoration Project off-loader, which transfers dredged materials from ships, is shown Friday, April 13, 2018. (Robinson Kuntz/Daily Republic)

The first phase of the Montezuma Wetlands Restoration project was approved Wednesday by the San Francisco Bay Restoration Authority board. It received $1.61 million.

The project includes “tidal and seasonal wetland restoration on 630 acres of diked baylands and enhancement of adjacent uplands in Suisun Marsh,” Restoration Authority documents state.

“The restored area includes 566 acres of tidal marsh and subtidal habitat, 45 acres of seasonal wetlands and 19 acres of high tide refuge and bird nesting habitat. Approximately 220 acres of adjacent uplands will be enhanced to improve upland habitat quality,” documents state.

The site, which is privately owned, is located in the Suisun Marsh, bordered to the west by Montezuma Slough and to the east by the Montezuma Hills, near Collinsville and about 17 miles southeast of Fairfield.

Part of the property is leased to the Birds Landing Pheasant Club and area ranchers for cattle and sheep grazing.

Jim Levine, with Montezuma Wetlands LLC, is the owner and heads the project. He said those lease areas will be adjusted from year to year as different lands are brought into the restoration area through what is now a three-phase project that will take 15 years to complete.

He called the public-private partnership the wave of the future and the most efficient way for these projects to get done.

“I don’t think a public agency could have done this project,” Levine said.

He expects the first phase to be completed sometime next year, he said.

The project was brought to the county in the early 1990s. The final permits – local, state and federal – were received in 2000 and 2001. The physical work began in 2003.

Levine said the company made a $15 million investment up front, and has contracts to haul dredged material from the Oakland Port to the restoration area, using barges up the Sacramento River, for about $12 to $14 per cubic yard.

The dredge work is part of the port’s goal of deepening the channel area of the port.

The Montezuma company’s first contract with the port was for 3.1 million cubic yards. Levine said. To date, it has hauled 7.5 million cubic yards. The total project will require 20 million cubic yards.

Concerns that some of the dredge material could be compromised by chemicals or other industrial waste, Levine said, has proven not to be the case.

“Most of the material we take is capable of being dumped right into the ocean,” Levine said.

If material dredged is tested at too high of a level of contaminate material, then it must be deposited into appropriate landfills.

That material that is tested above standard levels, but is still usable, is used as lower-level fill with cleaner cover material over the top that will be the base for habitat enhancement. A monitoring program is also required.

Using water from the Sacramento River, the dredged sediment brought to the area is turned into a kind of slurry material so it can be pumped. A series of ponds – or units – are constructed and raised back to a mix of historical levels.

Once that is completed, the levees are “punched open” to allow tidal flows through the channels that were also created to flow in and out of the ponds.

When the wetlands were first converted to grazing land and other uses, levees were used to block the tidal flow. The land then sunk, reaching levels of 10 feet or more below sea level.

“It is really a great place for restoration because back in the 1800s it was probably one of the richest Bay Area sites as far as ecological values,” Levine said.

Located in what is termed a “null zone,” it is an area where fresh water and salt water converge to create a brackish environment that supports a number of animals, and particularly a kind of brooding area for smelt and small salmon, Levine said.

“Several state and federally listed species including Delta smelt and longfin smelt, as well as other native fish, have been found to concentrate in this region of the estuary and will benefit substantially from the increased food production and habitat expansion provided by the project’s planned restoration of tidal marsh and subtidal habitat,” the project documents state.

“The restoration of tidal marsh as well as enhancement of remnant levee areas will also provide benefits to many terrestrial species, including three federally endangered species: salt marsh harvest mouse, Ridgway’s rail and California least tern; as well as the state-listed California black rail.”

In all, the authority approved $16.7 million in projects.

Measure AA, or The San Francisco Bay Clean Water, Pollution Prevention and Habitat Restoration Measure, created a $12 annual parcel tax over 20 years, generating $25 million each year and more than $500 million over the life of the tax.

The north quadrant, which includes Solano, Sonoma, Marin and Napa counties, is expected to get 9 percent of the revenues based on population.