Bicyclists beware.

Several of San Juan Island’s most heavily-traveled roads, including Roche Harbor and Beaverton Valley, will be covered by a sticky tar-like substance at various locations, and at various times, over the next 10 days.

That sticky substance is applied as the last step of the annual chip-seal program used by the county Public Works Department to better maintain and preserve its roads. The sealant, also known as “fog seal”, makes for a smoother surface, better visibility of road striping and reduces the amount of loose rock kicked up by automobiles.

It takes about 12 hours to dry, according to county officials.

Drivers should expect delays, as traffic will be routed into one lane as the fog seal is applied.

Bicyclists and motorcyclists can be more susceptible to having equipment marred by the sealant because of their closer proximity to the road surface.

Public Works Operations Manager Russ Harvey said the chip-seal program is on schedule and should be complete, weather depending, by the end of next week.

Click on the link that follows to view dates and locations where fog seal is being applied: http://sanjuanco.com/docs/hottopics/PW/118_2010ChipSeal.pdf