Hydroplane and Runabout racing boats will skim the surface of the Merrimack River this weekend for the Haverhill River Run.
Organizer Dave Goodwin, chairman of the Crescent Yacht Club's race committee, said interest in the speedboat races has grown since last year's return of the event to the Merrimack River for the first time in roughly 40 years.
This weekend, 80 racers from the United States and Canada — 20 more than last year — are expected to participate in 48 races, plus a marathon.
Races take place Saturday and Sunday from noon to 5 p.m. Most races start on the section of river across from the Buttonwoods Museum on Water Street.
The races are sponsored by the Crescent Yacht Club and the South Shore Outboard Association.
Haverhill River Run 2010 is an American Power Boat Association nationally sanctioned event.
The marathon, in which the boats will make several runs up and down the river, is the Northeast Regional Championship Marathon Race and the only marathon this season in New England, according to the race committee.
Racers will launch their boats at the yacht club. All spectators are invited to view the boats up close and speak with the drivers, Goodwin said. The yacht club will host a cookout open to all during the event.
The best spots for spectators are at the yacht club and on Buttonwoods Trail.
The stretch of river will be closed to recreational boaters during the races and will be patrolled by the Coast Guard Auxiliary.
