J-Mack Ferry

At the Grand Island landing, State Highway 220 runs down to Steamboat Slough and continues on a boat. The J-Mack is a cable-drawn ferry, 92 feet long and 32 feet wide by Caltrans’s figures. It carries up to six vehicles to East Ryer Island on a crossing of about 400 feet that takes about three minutes. Caltrans classifies the vessel as an extension of Highway 220. The ride is free, and it runs 24 hours a day, seven days a week, with boat operators on duty around the clock for individual passengers as well as motorists.

The landing lies about three miles west of the town of Ryde on Highway 160, and the slough is a county line. The crossing carries a car from Sacramento County into Solano. Ryer Island has two ways in by road. One is the J-Mack from Grand Island. The other is Caltrans’s second ferry, the Real McCoy II. It was built in 2011, is classified as an extension of Highway 84, and crosses Cache Slough from Rio Vista at the island’s south end with room for eight vehicles. A 2010 sidebar in the Lodi News-Sentinel, drawn from californiadelta.org, counted five Delta ferries still open to public access. Three of them led to islands that are private property, which left two free rides the public could take: the Real McCoy and the J-Mack.

The boat is not always on the cable. It went into drydock on September 29, 2024, for repairs and U.S. Coast Guard inspections, and in December a Caltrans spokesperson told WorkBoat it was expected back “by early January as originally planned.” In April 2026 Caltrans posted an advisory closing the J-Mack from May 7 to July 8, 2026.

Priest Island and Sutter Island

Ryer Island covers 11,700 acres and was named for a California pioneer, Dr. Washington M. Ryer, and his family. According to the News-Sentinel, citing an 1852 historical map collection of San Francisco Bay, a map prepared at the time of statehood shows the ground divided by the west fork of the Sacramento River. The western half is marked Priest Island and the eastern half Sutter Island. In 2010 Bob Songey, a regional manager for the California Department of Transportation, listed the island’s crops as grapes, corn, alfalfa, cherries, kiwi and others, all grown in soil he called rich.

The J-Mack was built in 1969. A Caltrans fact box printed in 2010 gave its size as 92 feet long and 39 feet wide, a wider beam than the 32 feet Caltrans lists now. The same box said the ferry was serviced in January and February.

A captain from Lake Superior

Margaret Iris Oberg, known as Peg, was born on March 13, 1940, at her family’s cabin in Grand Portage, Minnesota. Her father, Roy Oberg, captained boats to Isle Royale. After her children were grown she worked as a deckhand beside him on the Voyageur II and went on to qualify as a captain herself. According to her obituary in the Cook County News-Herald, she was visiting her daughter Debbie in California and “looking for adventure” when she took a job with Caltrans running the J-Mac, as the obituary spells it, across Steamboat Slough. The obituary says she “mastered the complicated process of on- and off-loading vehicles” and became the first female captain in what it calls the San Joaquin Delta area. Off duty she cruised and fished the Delta with Debbie’s family in her own boat, The Captain’s Kids. She later retired and returned to Minnesota’s North Shore, where she piloted the Summer Song on interpretive tours. She died on January 7, 2025.

Delta time, July 2010

In July 2010 a Caltrans worker greeted a News-Sentinel reporter and photographer as the J-Mack pulled out from Grand Island. “You’re on Delta time,” Songey told them aboard. “Things are a little slower here.” The ferry was then 41 years old and made about 200 crossings in a 24-hour period. Songey explained the round-the-clock schedule: because the crossing is part of the state highway, ending 24-hour service would in effect close a state highway.

The deck that day carried a cross-section of the people who use it. Michael Geredts of Pleasant Hill was taking his friend Lauryn Agnew of Moss Beach for a spin around the island in his bright red 1970 Morgan convertible. Clara Maria, 85, described as the oldest person born on Ryer Island, was riding off the island with her brother Joe, 76. Both still lived there. “It’s quiet; it’s a great place,” Joe said from his car. Three farm workers were headed home at the end of their shifts. Doug Gross of North Sacramento had brought his wife, Carrie, and daughter, Samantha, to see the Delta country where his late father had taken him fishing as a boy. “I’ve always liked coming down here as a kid,” he said. “We fished all over.”

At the controls was Capt. Paul Peretti of Sacramento, who worked 12-hour shifts back and forth across the slough. He told the reporter he liked the new faces and the new stories each day, and the otters and seals in the water. Once he saw a mink. The islanders kept him supplied as well. “These guys are bringing me stuff,” Peretti said, “like corn.”