There are numerous water faucet stations in Burlington, just pull up along one of them. If the spigots are not threaded, use an adaptor with a flexible silicone end to hook onto your hose and then onto the spigot. I recommend calling the Ranger Station directly to inquire re dump sites. Likely there is a dump station at one the many nearby state campgrounds to the north or south, the phone number is (707) 946-2409. You are likely aware, but just a heads up that there are some tight turns to make on the campground road, which is why they only recommend trailers up to 24'. The hiking in this park is amazing! Enjoy!