Most provincial & territorial campgrounds do not have services. Most have a communal hand water pump or water faucet.
At some of the busier B.C. provincial campgrounds there is a dumpstation on your way out, with a small fee for use.
In Yukon, the territorial campgrounds do not have dumpstations. For $12/night you get a great campsite and firewood for the firepit. Often by a lake so fishing is an option.
Most RV Parks in Yukon will let you dump your tanks and fill with water without overnighting. Free if you buy fuel. Small fee (usually $5-10) otherwise.
If you're needing to do laundry, the RV parks usually have the best and most affordable laundry facilities. So we plan a stay at a commercial park once a week to clean-up -- vacuum the RV and wash the RV, truck, humans, clothes. Before we leave, tanks are dumped and fresh water filled. Then we're good for another week.
Along the Alaska Highway, 3G is available only at Dawson Creek, Fort St John, Fort Nelson, Watson Lake and Whitehorse. They've announced that Haines Junction will also be upgraded to 3G, along with Dawson City. Other than those locations your 3G service will not work.
Internet access is also variable in its quality. Some RV parks advertise free internet and it means you must be in the office or laundramat hardwired to the outlet in the wall. For those that have wi-fi, it usually means sitting close to the office to get the signal and don't be surprised if you're bumped out of the connection often. A few RV parks have good wi-fi though. Free wi-fi is not easily found in Yukon outside of Whitehorse. Most RV parks limit usage to emails and casual web browsing due to the limited bandwidth; no uploads or downloads of large files. Don't expect high-speed browsing regardless.
