At the top of Thompson Park a smaller weir was built to supply water to the very popular boating lake in the park. This small weir also acts as a monitoring station for the Environment Agencies early warning flood system therefore altering the level of the weir or simply removing this obstacle to fish migration was not an option. A cheaper alternative to the construction of a fish pass is a fish easement where a series of small weirs in front of the barrier provide a way to gradually 'step up' the water level and make it passable. These improvements will also have a knock-on effect for other wildlife. Birds such as herons and kingfishers, and mammals such as otters, will be more likely to frequent the park knowing that there's a tasty meal to be caught!
Improvements to the fast flowing channel in Burnley Town Centre The rivers Calder and Brun have been forced to flow in a cobbled channel which runs for a length of 2.2 km through Burnley Town Centre. The channel is often culverted (built over) and some tunnel sections are over 100 m long. Both the fast flowing water in the channel and the dark culverted sections act as a barrier to migratory fish and offer few niche habitats for other wildlife. At an average speed in low flow levels of 1.9 cm/s the water in the channel offers no respite for fish attempting to swim through Burnley Town Centre. Our research demonstrates that at these water speeds, a medium sized fish (approximately 12 inches long) can swim for approximately 7 metres before it becomes tired and seeks a resting area. Larger fish will travel larger distances but not 2.2 Km without rest. To get photos of channel work and stone cairn into media and into the gallery below....
Fish Passes at Brun/Calder Confluence Weirs are a major issue for our rivers and the wildlife they support. They prevent fish from swimming upstream to spawn, and mammals such as otters must find alternative routes around them, often putting themselves in danger by attempting to cross busy roads. These two weirs at the confluence of the rivers Calder and Brun are visible from the bridge on Active Way in Burnley town centre. Having made all of the weirs downstream from Burnley passable to fish in previous years, these two weirs were next in line for modification. Two fish passes were constructed, one on each weir, so that fish can migrate further upstream through Burnley. Now there is the potential for more wildlife to enter Burnley's rivers, especially fish and the birds and animals that feed on them. In order to look after this asset,protect it and improve it, the idea for the Urban River Enhancement Scheme was conceived.
Improvements to river Calder Burnley Town Centre Edit photo gallery here to include in channel works - currently in gallery - need to put some into media The potential locations of the proposed habitat improvements in Burnley were carefully assessed working closely with the Environment Agency and carrying out a Flood Risk Modelling process to ensure that any changes to the water channel will help to alleviate flood risk in Burnley Town Centre.