The large drainage ditch that runs through the Harris Park neighborhood near West 72nd Avenue and Sheridan Boulevard in Westminster resembles one of those huge, concrete arroyos in Los Angeles that are notorious for suddenly filling with flash-flood waters -- along with abandoned El Caminos, stray dogs and Huffy-riding children. But Little Dry Creek lives up to its name and is usually no more than a foot-wide flow relegated to a narrow channel bordered on each side by large, banked walls. That's why the sections at the top, with a series of tall, concrete wedges and an oversized launch ramp, have been a prime unofficial spot for local skaters since the '80s. But ever since the site popped up as a major destination on Thrasher magazine's King of the Road tour, pros and bros from all over are heading to the ditch -- and keeping an eye out for storm clouds.