You can find the local frequencies for the RCMP in the database on Radio Reference. Here is a link to a list of the old RCMP VHF frequencies used province wide in Saskatchewan.
http://www.radioreference.com/modules.php?name=RR&aid=2045
As I said, those are the old frequencies. You will find Big River using Ch 9 (Local) for car to car communications, and one or more of the other frequencies for longer range communications. Plug in all 12 channels (don't bother with the "Input" frequencies) and start scanning. You should hear something, unless they've moved to the new system.
The RCMP in Saskatchewan are moving to a new digital VHF trunked radio network. Right now they are using both the new and old systems. I do not know if Big River has been converted to the new system yet or not. The new system is P25 digital, so you will need a digital scanner. There are a few frequencies for the new system in the database.
http://www.radioreference.com/modules.php?name=RR&sid=4632
The frequencies for the new system should be in the 138 to 140 MHz range. I would search that range, looking for a digital control channel signal. The control channel signal will be a continuous data signal, and should not be hard to find. You will have to continue to search the same range looking for the voice channels though. There may be 4 or 5 of them.
Hope this helps.
Rob
Regina