Multiple free dump stations near Los Angeles are conveniently available. One of these is at the Lake Perris Service Rest Area, which is 28 miles from the San Bernardino National Forest. Another is located at the Silverwood Lake Service Rest Area, which is just 18 miles from the San Bernardino National Forest. You could also take advantage of the free dump station at the Riverside Sewer Treatment Plant, which is 50 miles east of Los Angeles. The Lee Lake Water District also has a free dump station 55 miles east of Los Angeles.

If you camp at Bolsa Chica State Beach, then you can use their dump station for free; otherwise, you'll need to pay $10 per use. You could also use the dump station at Doheny State Beach, which costs $15 for the general public to access.