I generally agree with the concept of user pay but, and its a BIG "but" and a learned caution due experience. Two cases to point:
On the Tonto National Forest about a dozen years back, The FS, with general NGO and user groups approval, installed their "Fee Demo" program on the local lakes and rivers. Their claim then was the monies would be used for law enforcement, facilities maintenance, ect.
Today, the major law enforcement effort is to cite persons who do not pay the fee and a good bit of the maintenance money was spent to build access denial structures and force every one into pay camp areas. If I had to do it all over again, I would be demanding those dollars ONLY went to the originally designated uses.
Case two is Arizona's State Lake Improvement Fund (SLIF) which is a boater public self-imposed, approved by the state legislature law that taxes boat fuel and other boating supplies. SLIF dollars were to be maintained by Arizona State Parks and used as match funds for agencies to provide better access, construct launch ramps, picnic facilities, bathrooms, garbage collection, maintain hazard markers, ect. What a joke it has become, 15 years ago, the legislature simply took general fund dollars away from State Parks in the same amount that came in thru SLIF thus forcing Parks to use those dollars to keep the lights on. We still pay the tax but get nothing in return.
While I do generally agree with user pay and see the need and would support a fee to maintain access roads, I have learned the hard way that those dollars tend to go to other uses especially when they are accumulated into a large account as the proposal letter states. All NGO river orgs. and individuals need to be in front of this and get solid assurances up front along with a bomb-proof agreement that will stand in court cause some crafty polititian or agency head will make the attempt to divert the money.