BIDDEFORD/SACO — The Biddeford Saco River Jam Festival, celebrating life on the Saco River, is bringing a host of activities to Biddeford and Saco on Sept. 14 and 15.

River Jam is hosted by Heart of Biddeford and Saco Main Street, in partnership with Engine, the Biddeford+Saco Chamber and the cities of Biddeford and Saco, and help from local sponsors.

“This is River Jam’s fifth year and it’s really growing in popularity,” said event co-host Delilah Poupore, executive director of Heart of Biddeford.

Organizers expect 4,000 people to attend the weekend’s activities, Poupore said.

The festival kicks off Friday night with Fringe Fest from 5 p.m. to 9 p.m. on Main Street and at Shevenell Park in Biddeford. Fringe Fest goers can listen to a performance by Dark Follies, sample items from local breweries and restaurants and join in on a “Pie Luck” — a free potluck of pies available to all who attend.

“Fringe Fest gives a spotlight to theater, dance, puppetry, music, visual arts, and spoken word. It’ll be an arts smorgasbord,” said Tammy Ackerman, director of Engine, the community arts group hosting Fringe Fest.

Also on Friday is the opening of “Influx: A Multimedia Installation Event,” from 5 p.m. to 8 p.m. at Pepperell Mill Campus. The art installation will feature work inspired by the past, present and future of the mill, the natural elements of the nearby river and ocean, as well as the activities of the people in the mill and surrounding urban areas. Artists will be present at the opening event, and patrons will be able to download a free mobile app —Milla — that will enable them to locate art installations and performances with indoor mobile wayfinding.

Saturday’s events start with the annual River Jam 5K Road Race at 8 a.m., with registrations online at RunSignUp.com. Runners can come out for a fun run or compete for prizes. Advance registration is $20 and day-of registration is $25.

The Biddeford Recreation Department will host the “Dash to the Sea” kayak race on the Saco River at 10 a.m. on Saturday. All registration materials are available on the Biddeford Recreation Department website. Registration is $15.

River Jam co-host and director of Saco Main Street, Robert Biggs is enthusiastic about the events on the River.

“I get to spend Saturday morning on the Saco River during the Dash to Sea. It’s the river that ties these two communities together, so it’s only fitting that we get out and celebrate it together. Whether you watch a kayak race or get out on the river to try out a canoe, you’ll get to enjoy this beautiful part of our community,” Biggs said.

A variety of free events will be held from noon to 4 p.m. at Mechanics Park in Biddeford. There will be performances by Sellam Circus, children’s games, a curated Makers Market, BBQ lunch for sale and 20 community booths. There will also be free canoe rides on the Saco River leaving from Rumery’s Boat Yard, just down the block from the park.

River-lovers can also purchase tickets for $20 on Eventbrite for boat tours down the Saco River that leave Rumery’s Boat Yard at 1 p.m., 3 p.m., and 5 p.m. on Saturday.

Gates open for the Main Stage on Saco Island at 4 p.m. on Saturday night, where a beer tent and food trucks will welcome visitors for an evening of live music beginning with Portland band Snughouse. Next up will be Bri Lane, last year’s winner of the River Jam Battle of the Bands, followed by Sylvain’s Acadian Aces and ending with As Fast As.

More details are available at www.RiverJamFest.com and Facebook/RiverJamFestival.