Last time been there Mar 5-7 for 2 nights. Water level in the lake is full, from the Devil's backbone trail seen a bunch of huge (2-3 feet) fish, probably carp or bass. Regretted I didn't take my kayak and a fishing gear! There is huge amount of waterfowl, including large geese and ducks, a lot of annoying squirrels as well ;)
That time park was open 75% as per the rangers, but I hope it is now 100% after the Mar-10. The only downside they don't have a full hookup sites so if you are staying longer than a couple of nights in your RV, be prepared to travel to a dump station every other day or so. On an opposite side the newly built (and renovated) restrooms with showers are top notch! Way better that a 4-star hotel, seriously! Very clean and well maintained! Overall the park is very well maintained! There is a number of cabins along the lake just across the marina and the gift shop. There is also option to rent a kayak or a canoe, but it was closed due to CCP virus.
Very nice RV resort! Full hookup, concrete level pads, huge pull thru sites, great for large rigs. A lot of amenities: playground, tennis courts, hot tub, pool, clubhouse. Very polite and attentive personnel! Only a few miles (10min driving) from the ski slopes. If winter camping - heated water hose is highly recommended! During especially chilly nights be prepared to fill up your fresh water tank and turn off and disconnect the hose from the external water supply! If it is frozen overnight, you will be subject to $150 fee.