Trout in the Trym

Trout in the Trym is a grassroots group aiming to improve the ecology of the River Trym, North Bristol. This is a small (6 miles long) urban stream flowing through a town centre, council estates, parks and green spaces. Whilst potentially a real asset for wildlife and the public, it's been blighted by rubbish, pollution, numerous weirs, you name it. In a word - neglected.

Volunteers are trying to make it better for wildlife and a nicer feature for locals to spend time by (80,000 residents live within a mile or so, including several pockets of real deprivation). The main focus has been on rubbish clearance, litter picking and Himalayan balsam removal, with groups of volunteers tackling these from source to mouth for the last 5 years. Volunteers also report pollution incidents to Wessex Water (if sewage is suspected) or the Environment Agency (oil, dead fish, etc). Since the work started:

• pretty much every metre of the river has been cleaned at least once (over 400 tonnes of rubbish removed, including 16 motorbikes);

• members have spent 1,000 hours pulling balsam (it is in retreat);

• 30 separate pollution events have been reported with precise locations and photos given (and some infrastructure improved as a result).

Bristol Avon Rivers Trust (BART) helped locals establish Riverfly sites on the Trym in 2021, in different parts of the catchment. The goal is to be on the front-foot in event of a major pollution incident. Meanwhile Riverfly results and pictures of invertebrates (and bullheads) in the samples are shared on the website and Facebook group, which people like. This reinforces the connection between the work being done in their community and wildlife in the water. 
Volunteers are doing everything that can be expected of them, with Riverfly part of this. What's also needed to really improve the river is for other major stakeholders to pick up the baton. 

To help, the Trout in the Trym also uses Riverfly data as part of its approach to measuring the health of the river. Some years ago, Bristol City Council set a goal of all Bristol's rivers having clean enough water for healthy wildlife by 2030. However, the group found out they hadn't put in place any reporting (so didn't know where or how big any problems were or what was causing them). To plug the gap, a volunteer put together a one-page River Health Dashboard which uses Riverfly scores as one of the key measures (plus also CSO data 'Is my river fit to play in?' and Riverblitz Phosphate/Nitrate levels). The report has been shared with the council and others for the last 2 years. Progress is beginning to be made with the council and local catchment partnership (who now plan to start reporting river health officially). Regular Riverfly sampling and reporting has enabled us to demonstrate there is worthwhile wildlife already - but also that there are real issues to be addressed. Data is so much stronger than people's opinions.

Another benefit of Riverfly monitoring is that more individuals are knowledgeable, committed to the welfare of their local river and vsiting it often. As an example, one of our monitors realised there was a build-up of silt at their site. Leaders of Trout in the Trym looked into it and wondered if it was running off huge building sites upstream. This was reported to South Gloucestershire and the EA, who are formally investigating. We wouldn't have spotted this (or at least, only eventually, probably months later) without our monitor regularly spending time in the river and getting to know their patch.

In summary, Riverfly is an excellent initiative and we encourage other groups to use the process and data from it as fully as possible as a safeguard against pollution and for wider purpose

Peter Coleman-Smith, Trout in the Trym