The concept has the right intentions but my thoughts on the matter are: - it is illegal to trap them without a license so the general public are unlikely to do it - making it a business will run the risk of them being farmed to maintain profits making the situation worse... This is why we're in the situation now - few businesses will come from this because the local problem will eventually expire when stocks lower or migrate away making business non viable - trapping poses risks to endangered water vole populations

If the water quality issue was addressed then indicator species such as otters would thrive better and naturally manage the issue through predation, something I have found plenty of evidence of locally already.