Riverside tree and scrub management
Management of riverside tree and scrub is a complex task for the Authority as we seek to balance the interests of navigation with environmental conservation.
The river corridors of the Broads contain a variety of habitats, with trees and scrub occupying a significant proportion. This wooded environment provides valuable habitat for birds, fish, bats and otter; forms an important landscape resource; and contributes to ecosystem services in the form of carbon storage. However, encroachment by trees and scrub over and into the water causes safety issues for navigation through the narrowing of the navigation channel and obstruction to sight lines, particularly on river bends. Dense growth of trees and scrub also has the effect of reducing the amount and strength of wind available for sailing vessels.
Some management of riverside trees and scrub is required in order to maintain navigation use and safety, however, the needs of navigation need to be balanced with the other values and interests as noted above. This balance can be achieved through effective prioritisation, consultation and sensitive working practices.
Much of the Broads area is designated for its nature conservation interest at National and European level. As such, any works within these protected areas requires assent from Natural England before work can commence. Consultation is required with the Environment Agency as riverbank tree management falls within the scope of the Water Framework Directive (WFD). An Environmental Permit is also a legal requirement for the use of herbicides near waterbodies, which includes the treatment of cut tree stumps. In addition, the Forestry Commission must be consulted on large scale felling of trees through the felling licence process, although the Broads Authority is exempt where works are required to maintain navigation safety.
In 2015, an approach to categorising and prioritising riverside tree and scrub management was produced by the Broads Authority. Each river valley was surveyed by a Ranger and Environment Officer to determine the types of habitat present and the work required to make improvements to navigation safety. For each stretch of the river a priority class was assigned to reflect when the work should be undertaken. Notes were also taken regarding ecological features such as trees with bat potential and other points of conservation interest.
During January 2017, Rangers and Environment Officers worked together to fine tune the prioritisation process with additional criteria added to improve the robustness of the process.
The list of parameters utilised in the prioritisation process includes:
- Sailing intensity
- General boat usage
- Presence of moorings
- Position of river stretch (bends or straight)
- Density of riverside growth
- Width of channel lost to tree encroachment
Specific boat use in certain areas such as sailing regattas, rowing clubs and boat testing stretches will also be captured as part of the prioritisation review.
Following the prioritisation and mapping process, permissions from statutory bodies and landowners have been obtained. Natural England assent covers the 5 year work plan, whereas landowner permission is sought on an annual basis once the fine details are determined in the summer preceding the works.
Prioritisation areas (2017 - 2022)
Prioritisation area maps for year 3 (2019/20) can be found below based on river:
The prioritisation has been used to produce maps showing those areas that require management within the next 5 years.
We are currently in the third year (2019/20) of the five year programme. Years 4-5 (2019/20-2021/22) are subject to final operational work planning and budget availability in addition to obtaining further landowner permissions.
For each consecutive year, final decisions will be made over the summer as to the exact stretches that will be managed the following winter and how they are best managed in terms of resource. As part of this process, all areas of completed management will be recorded and any stretches that do not get managed within the proposed year will be re-programmed.
It is anticipated that a further re-prioritisation exercise will take place during 2020/21 to plan the next five year work programme commencing in 2022/23.
Caveats for Maps
All information shown on the maps are subject to landowner permission.
Works for 2019/20 have been agreed but all future years may be subject to change.