What you should look out for when you see a new proposal:

intention to build dams or divert water (e.g.: the proposed Kipawa dams threaten the Dumoine river because both rivers share the same headwaters) A dam is a significant change to nature and has no place in or to affect parks.
if there is a dam - how are water releases managed? This is a bit controversial, even amongst paddlers: the whitewater play folks typically want reliable water flows throughout the summer. As an environmentalist, I would like to let nature dictate the flow, without man's interference, so that the native habitat can survive. Then, as a canoe traveller, I will cope with what nature throws at me.
do ATV’s and roads present a problem to your area? E.g. if an area is designated "remote access", point this out to the MNR; they are under obligation to keep it remote and stop motorized access. ATV's should always be kept from portage trails by the regulations, as they churn up the ground and turn slanted paths into miniature creek beds. Beyond that, the ATV's noise, the  pollution from fuel and exhaust, and the trash they bring cannot be reconciled with "wilderness". See the ATV page for details
is a "Forest Management Plan" up for review? That's a big one, but review it if you can find the time and energy. Look to see that portages, shore lines and viewsheds are protected from cutting. Look for planned roads and their impact, replanting efforts (native species, and mix?).
is access to the route maintained You want to be able to get to the canoe route, but this can be a two-edged issue. If you have access, the proximity to water and the parking space attracts other users as well. E.g., in the case of access to Obabika Lake, I finally agreed with the ministry not to create a public landing because that would in the end destroy the wilderness character of the lake. My rule of thumb: put at least one portage between road and canoe route!
are park and access fees fair Interior fees should be significantly lower than camp ground fees. If an access fee is charged and the route is maintained (portages, campsites) by some organization, I don't have a problem paying a reasonable fee. Also, a canoeist as a low-impact user should never have to pay the same as a power boater for the use of the waterway.
are gravel pits planned at or near the canoe route The landscape will not only be scarred and subject to erosion, but the truck traffic with its pollution is a threat to the surrounding wilderness
are new bridges being built across the river A bridge means not only the potential end of wilderness character, but its associated road destroys an ecosystem that depends on a closed forest canopy. Non-native animal and plant species can take a hold and permanently alter the environment

         Issues that you will be running into:

Many local people's jobs and lives depend on resource extraction. Avoid futile confrontations and rather look for common ground.
Respect other users. It is not only correct but also prudent, as hunters and fishing folks have rights just as you do.
Access control needs to be worked out with canoeists and other users. The contention for a week's reservation that we are seeing already in the popular parks will become the norm. Eventually, but surely.
Cleanup may need to be initiated in an area. See who does it now, and offer to participate. Is it a good idea to initiate some on your own? If you do, solicit help from others and let the "players" know you are doing it; you might as well reap the mileage that you have earned.
Hunting in the parks I see two issues here and no easy solutions.
First, you may have an ethical problem with killing animals for sport, just as I do. But I realize that I cannot force people to live by my ethics, just as I resent it when someone tries to manipulate my values.
But there is a safety issue with hunting near canoe routes, camp sites and portages. Sure, hunters in general are responsible and will take precautions to avoid accidents, just like drivers. But we have learned to separate cars from pedestrians for safety reasons, and it's valid to request that hunting is kept away from areas where they can be a threat.
The political scene (in Ontario) is in favor of hunting, and the government has elegantly sidestepped the blame. Most parks are now (after July 1999) free to implement hunting. They'll do it via public consultation and many local folks will side with the hunters. If you cannot succeed on moral grounds, go for the safety angle.
Portages may not marked properly. Approach the MNR and ask whether they mind if you put up portage signs. Ask for advice how to do it (just tacking the signs to trees is not a durable method) and they are likely to supply signs to you.

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