Case study:River Tarrant Rehabilitation Project
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- 1 Project overview
- 2 Image gallery
- 3 Catchment and subcatchment
- 4 Site
- 5 Project background
- 6 Reasons for river restoration
- 7 Measures
- 8 Monitoring
- 9 Additional documents and videos
- 10 Additional links and references
- 11 Supplementary Information
|Project web site|
|Themes||Environmental flows and water resources, Habitat and biodiversity, Water quality|
|Main contact forename||Sarah|
|Main contact surname||Guest|
|Main contact user ID||User:RachelM|
|Contact organisation||Environment Agency|
|Contact organisation web site||http://www.gov.uk/government/organisations/environment-agency|
|Parent multi-site project|
| This is a parent project
encompassing the following
A very uniform 500m section of the Tarrant, with extremely limited existing habitat diversity, was modified using a number of different techniques. The main work involved re-profiling the bed to create some variation in long and cross-section. No re-profiling of banks was undertaken, nor did the work involve any land-take. In the upstream sub-sections A-B live willow logs/stakes were also installed into the river or up the bank slopes in specific locations.
The physical modifications of re-distributing bed material around, installing log deflectors and occasional short stake to form pollards, was completed in just over two days. Work was completed within four days by wiring down firmly each of the installed willow logs and cutting pinning stakes back to log height.
Monitoring surveys and results
Monitoring was completed before works to detirmine where works should be focused. Monitoring was also completed after the works to establish how successful the project had been.
At the very least periodic visits to the site should be made to help ensure grazing management is ideal for the conditions that develop. Repear photographs are recommended for the archive. Biological monitoring may be of limited value if pre-conditions have not been recorded.
Providing cattle and sheep do not have access to the channel on a permanent basis, the created features of pools, runs and low-flow self-cleansing sections will not only be sustained, but improve over time. The hoped for growth of willow to form both habitat and landscape improvements has less chance of guaranteed success - the logs and stakes have been left far too long (over seven months at least) for ideal use. They have also been installed much later in the season than is the norm to encourage sprouting and rooting. When installed in the dormant period, or spring / early summer, sprouting is accompanied by rapid root growth - both will be limited now, and roots may not have sufficient dampness to succeed.
Keeping the banks fenced for two years will be ideal if any growth of willows is to reachits maximum potential; thereafter periodic grazing will help keep lower branches in check and be good for all other aspects of the marginal vegetation (as well as restore full grazing potential)
Catchment and subcatchment
Select a catchment/subcatchment
Other case studies in this subcatchment: Tarrant Monkton Rehabilitation Project
Cost for project phases
Reasons for river restoration
Hydromorphological quality elements
Biological quality elements
Physico-chemical quality elements
Additional documents and videos