If you’re planning to drive a trailer, RV or even a small sports car onto a ferry boat soon, the Washington State Ferries advises you check its Web site first to make sure a low tide won’t hamper your trip.

Until July 3, the WSF warns that the “extreme low tides the Puget Sound will be experiencing” will make it difficult for some vehicles to get on and off its boats.

When tides are –1.5 or below, the agency explains it is “unable to load low-clearance or extended vehicles at many ... terminals because the loading ramp becomes too steep and these vehicles have difficulty clearing the hinge point as they cross from the dock to the ferry.”

To prevent problems, WSF will have load restrictions on certain sailings for those vehicles with low ground clearance or vehicles that have “extended rear bumpers or trailers, including RVs, commercial trucks and some small sports cars.”

The agency admits restrictions may affect certain ferry users’ summer travel plans, but reports that this is an annual occurrence.

“Every year we have this period in early summer where the low tides are such that we need to limit low-clearance vehicles,” said Steve Rodgers, director of operations for the WSF. “We will do everything we can to accommodate all travelers with a minimum of inconvenience, especially as we approach the busy Fourth of July holiday.”

Vehicle restrictions will be in place for a two-hour window before and after the extreme low tides, which WSF said are expected to occur during the morning and midday periods through July 3.

Low tides — and heavy traffic — affected the Southworth-Vashon-Fauntleroy route both Saturday and Sunday last week-end, according to several alerts e-mailed to riders.

On Saturday, riders were advis-ed that both the M/V Issaquah and M/V Sealth were running 20 minutes behind schedule due to both “heavy traffic and tidal conditions.”

Motorists were advised to ar-rive 60 to 90 minutes prior to departures.

The Triangle route experienced similar problems on Sunday, as alerts warned that the M/V Issa-quah was again running late — the 12:30 p.m. Southworth departure did not leave until 1 p.m. With continued heavy traffic and low tides slowing the loading procedures, Issaquah reportedly began running 40 minutes behind schedule, and motorists were again advised to arrive about an hour before sailings.

An e-mail sent at 5:22 p.m. informed riders that both the 4 p.m. sailing from Fauntleroy to Vashon and the 4:25 p.m. sailing from Vashon to Southworth were cancelled to get the schedule back on track. However, the alert said the vessels were still “operating 5-15 minutes behind schedule.”

WSF will post specific restric-tions and low-tide information for all ferry terminals daily on its Web site, http://www.wsdot.wa.gov/ferries/, and encourages travelers to check the latest information before starting their trip.

Low clearance vehicles that arrive at the terminals during the low tide windows will be held until a later sailing.

Low tides are expected at these times: June 29, 10:15 a.m. to 11:45 a.m.; June 30, 11 a.m to 12:45 p.m.; July 1, 11:30 a.m. to 1 p.m.; July 2, 12:15 p.m. to 2:15 p.m.; July 3, 1 p.m. to 2:30 p.m.

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