River Restoration and Habitat Enhancement
RRC
The River Restoration Centre’s key role is to promote the concept of best practice management and river restoration. It provides information and impartial advice based on the expertise of its staff and external advisors, an inventory of over 1500 projects collated by the Centre, and a UK-wide perspective based on knowledge gained over
the last 15 years.
Restoration and enhancement
River restoration and habitat enhancement is a means by which we can turn around the past trend of damage and degradation of our riverine ecosystems. Many are no longer attractive or desirable places for the wildlife that they once supported. Urban and rural rivers have both been affected, by the dominant activities that were perceived to be the priority at the time. By applying what fluvial-geomorphology tells us about the physical riverine system and what ecology tells us is needed for a diverse range of habitats and species, we can assess and respond to the need for conservation, enhancement or restoration of watercourses and floodplains.
The River Rhee
An upper reach of the River Cam,
Cambridgeshire, the River Rhee is a good example of a degraded lowland
agricultural river. A baseflow fed brook, once containing a healthy population
of wild brown trout, it is now lost in its deepened channel and suffering severe siltation problems. An initial visit examined the opportunities
for achieving floodplain restoration, and bringing visual and hydrological connectivity to the river. However, after critically assessing land, river and water levels it was concluded that floodplain restoration would not be
possible in the main area proposed without having an impact on neighbouring farmers, and the adjacent road. This can often be a major limiting constraint.
Due to the history of 'improvement' to land drainage (dredging the river deeper and frequent follow up work) there was also plenty of scope to enhance the bankside and in-river habitat. Habitat enhancement works included channel narrowing to uncover the gravel bed, shallowing the profiling of banks and existing meanders to remove years of dredging material and nettle growth, and off-river backwater habitat creation as a refuge for fish and invertebrates in times of flood. These were identified as options by carefully ‘reading the river’ and both aiding its natural recovery (which could take centuries in a lowland clay catchment) as well as removing obstacles to recovery (spoil embankments, steep slopes, etc).
The works were funded by the
Environment Agency and delivered by Roger Beecroft Wildlife and Countryside Services with support from RRC.
Benefits
Although a small scale scheme, this project has great potential as a demonstration site showing best practices for managing and rehabilitating previously heavily engineered rivers in flat, arable landscapes at low cost. The landowner has a river he can now see without having to fight through nettles and peer over raised banks. The silt has washed off of the gravel bed increasing fish and invertebrate habitat; the shallow marginal shelves support typical river’s edge plants and the stripped shallow banks are developing a more typical nutrient poor grass/wildflower cover.
Martin Janes, Managing Director. www.therrc.co.uk
Updated information February 2017
This case study features in RRC’s Fixed Point Photography Factsheet and Video. Find out more here: http://www.therrc.co.uk/supporting-uk-trusts-partnerships-and-community-groups-0
See more case studies at http://www.therrc.co.uk/case-studies
Updated information March 2020
Contact the River Restoration Centre for advice at any stage of your restoration project at rrc@therrc.co.uk, or visit our website for more information on river restoration projects, training courses and guidance material www.therrc.co.uk