Greetings from Montana. Here is some more Yellowstone Bridge Bay Marina/Lake Information to add to the previous post by others.
1. Inspections and permits - Boats must be inspected by a resource Ranger at the Bridge Bay Marina Ranger Station before they can be launched. Inspections close at 4

M, the Ranger Station closes at 4:30 pm, this is where you will get both your boat permit and inspection sticker. Same goes for kayaks and canoes.
2. Marina office - Usually open till 5:00 pm or much later early in the season, this is where you pay for your slip (this is not the same people that provide the boat inspections and back country permits). 307-242-3876
3. Restrooms – The NPS maintains heated restrooms at the marina, a bit crude and no hot water. The Lake Lodge has a laundromat and nicer restrooms.
4. Showers- Showers are at the Fishing Bridge RV Park about a 15 minute drive north from the marina. I think they are around $4.00 -
http://www.yellowstonenationalparklodge ... ge-rv-park
5. Power - At the marina there is shore power and water. You will need the special 30 - 40 amp marine plug to connect to shore power (not the same as an RV park plug/adapter, there is no 110v outlet).
6. Docks and slips – The docks are super high quality, they look like teak. Since the recession they never fill the marina. B-dock is the transient dock and all the slips hold 2 boats. If you want a single boat slip (your neighbor can’t bang into your boat) just pick out a vacant slip when you get there and ask if it’s available.
7. Backcountry permits - To spend the night on the lake in the back country (not at the Marina) you will need a back country permit. Back country permits are no longer free, this year for the first time they are charging $3.00 per person for a back country permit -
http://www.nps.gov/yell/planyourvisit/b ... hiking.htm
8. Backcountry docks – Unfortunately the Feds don’t allow you to anchor out on the lake overnight anywhere you chose (this is a highly protected environment), you have to be assigned a permit for a specific anchorage/dock site. There are 3 back country overnight docks, one day use only dock and several anchorages. Listed here -
http://www.nps.gov/yell/planyourvisit/u ... r_2012.pdf
9. Dogs and Cats - Pets are allowed on the boats but not off the boat on a backcountry beach or at a back country boat dock.
10. Bears - If you plan on hiking on any trail you will need to have bear spray. To wonder around without bear spray is like boating with no PFD on board. Bear spray is available in all the park stores approx. $35.00 - $45.00.
11. Major shopping - Cody Wyoming is 80 miles east, lots of stores and museums. The park stores are pretty well stocked -
http://www.codychamber.org
12. Cell phones – There is cell service in the marina now thanks to a recent and very controversial cell tower. BB service available with a booster in the marina, without a booster out on the lake.
13. Restaurants – The Lake hotel restaurant is upscale and swank. Live piano music in the lobby and a fun place to just hang out and enjoy the evening and a view of the lake. Around the corner is the Lake Lodge, rustic atmosphere with a roaring fire on cold days and a very nice cafeteria that is reasonably priced, lake view dining on a budget.
14. Lodging/cabins – Things book up a year in advance as others have noted. Sometimes you can get lucky if there are cancellations. Check back often as things do change. You can boat camp in the campground at the marina as an option if you arrive too late to get in the water -
http://www.yellowstonenationalparklodge ... dge-cabins
15. Weather - September can be very cool in Yellowstone (mornings in the 30s), bring a heater. We run our shore power heater every morning July, August and September.
Some feel it’s a hassle to get all the permits to boat and stay overnight in the backcountry but it is well worth it. The NPS struggles with balancing preservation with recreation, It’s a tough job. Whatever the hassle and cost, it’s been very much worth it for us. I worked in YSNP in 1978 and took my first paddle on YSL that year. We boat, camp, hike or ski in the park just about every month of the year. There is nothing like floating your boat on the top of the world’s largest active super volcano, surrounded by the largest concentration of wolves and grizzly bears in the lower 48. Come visit and enjoy.