Visitors who arrive in Avalon Harbor from the mainland are frequently amazed at the crystal clarity of Avalon Harbor. Along the breakwater, the view of bright orange garibaldi, tabby-cat colored calico bass and bluish-grey opal eye can rival those seen in public aquariums. Kelp undulates in amber-colored forests and the normally private lives of ocean-dwelling animals are on public view.

Many of Avalon's visitors have left the mud-colored, trash-strewn, seemingly lifeless waters of Long Beach, Marina del Rey or Newport Beach. For them, arriving at Catalina and seeing the sandy bottom of Avalon Bay 30 feet below their boats can come as a revelation.

One of the many reasons for those clear waters is the Avalon Harbor Department's dye tab program. Instituted in the late 1980s, the dye tab program was begun soon after the Los Angeles County Health Department shut down Avalon Bay on a Fourth of July weekend because it was unsafe for swimming. Desperate for a solution, the Avalon City Council put together what was then an innovative solution to make sure boaters weren't emptying their sanitation systems into the harbor. The result of their efforts was Avalon's dye tab program.

Each private vessel that enters Avalon Harbor is boarded by a harbor patrol officer who inserts a dye tablet into all of the boat's toilets. Those tabs, which start out orange, are formulated to turn a vivid, unmistakable green when they mix with salt water. Before the patrolman leaves, a test flush is conducted to make sure everything is working properly. After that, if the distinctive green dye appears in the waters around the vessel, the ramifications are severe. First, there are criminal fines handed down by a judge. But more significantly, at least for frequent boaters, the vessel is banned from mooring in Avalon Bay for a year. There are no exceptions, whether for faulty equipment, ignorance of a new system or drunken boat guests.

Boaters who plan to spend the weekend-or longer-have two options to empty their holding tanks. The first is to do the job themselves at Avalon Harbor's pump-out station. Located on a float near the Casino Building, the pump-a-heads are complementary and open 24 hours a day. For those who would rather pay someone else to do the dirty work, Head-Pumpers will come to the boat and empty the sanitation system. Head-Pumpers can be hailed on VHF channel 68.

Either way, after the holding tank is empty, if the vessel is going to remain in Avalon, its skipper can expect another visit from a harbor patrolman bearing more dye tabs. Boaters who leave their mooring for the afternoon, perhaps for a cruise along Catalina's beautiful coastline, can also expect to have their heads re-tabbed.

Sherri Walker Cline