RSPB Rotary Ditcher Conservation Project

Overview

It is owned by the RSPB and operated by specialist contractors, RC Baker Ltd. It is available for hire for wetland conservation projects throughout the UK.

Objectives

In 2002 the RSPB highlighted a need for a machine which could help in restoring some of the wet features which were traditionally found in grazing marshes. After a lot of searching, the first rotary ditcher was purchased from the USA with support from the Heritage Lottery Fund. The original machine was replaced through a successful WREN grant application in 2013.
The ditcher is most efficient at creating 'foot drains' - shallow channels designed to hold surface water. These areas provide habitat for breeding waders, such as lapwing and redshank, and their chicks - which feed on invertebrates in wet mud at the edge of pools and scrapes. Soil type, topography and water level management are all important in designing foot drains.
Research carried out by the RSPB has shown fields with high foot drain densities attract significantly higher densities of nesting lapwings.
Waders prefer to nest closer to the edges of footdrains as they provide suitable food for chicks as soon as they hatch.
Lapwing chicks are more likely to feed nearer foot drains, on wet mud created by receding water levels.
It is also widely accepted that having isolated small areas of water in fields, significantly increases the number of wintering waterfowl in an area.
Reference: Eglington, S.M., Gill J.A., Bolton M., Smart M.A., Sutherland W.J., Watkinson A.R. (2007) Restoration of wet features for breeding waders on lowland grassland. Journal of Applied Ecology, 2007

Planned Work

Landowners and site managers are giving nature a home by hiring the machine to create wetland habitats rich in wildlife. The annual work programme is in constant development, with projects usually planned across the UK.

The rotary ditcher is a vital tool for creating wetland habitats at a landscape scale. The machine has worked across many of RSPB's Futurescapes, with more work planned in the coming years.

Results

The rotary ditcher:

Can create foot drains 3m wide at a rate of around 200m per hour* - ten times faster and half the cost of an excavator

Is laser-levelled to give an accurate depth of excavation, with adjustable cutting blades to create variable ditch edge profiles

Creates ditches up to 6m across by up to 1.5m deep with more passes*

Throws spoil up to 30m away*. Spoil breaks down easily into the sward and gives a good tilth for reseeding if required, or it can be left to allow grass to grow through.

Creates pools 10m wide and up to 30m long, with a maximum depth of 30cm, in less than an hour*

Shifts up to 10 tonnes of spoil per minute*

Can be used to lower bed levels, material can be loaded into dumpers for removal or throw to targeted areas.

*Depends on soil type, topography, vegetation cover and complexity of features being created.

Hire costs

The ditcher is primarily based in Oxfordshire. It has to be transported on a low loader between sites that are more than 30 miles apart. This can make up a significant amount of the cost, but all attempts are made to keep this as low as possible.

To do this, the annual work programme is designed where possible to group sites together to share haulage costs.

Limitations

Due to the size and weight of the machine ground conditions have to be dry.

The machine is most suited to hard soils such as clays and loams with wet peat soils being best avoided. Alternative machinery is available for these sites and this will be discussed during the site visit.

Advice and booking information

The RSPB can provide free advice and support on the deployment and use of the ditcher, including undertaking specific site visits. The machine and its operation are complex and such support is often a vital element of project success. Sites interested in booking the Rotary Ditcher should be aware that to obtain the maximum value for money advance booking is essential.

Previous clients

The rotary ditcher has worked on many RSPB nature reserves across the UK, These include Minsmere, Titchwell Marsh, Otmoor, Berney Marshes, Ouse Washes, Greylake, Exe Estuary, Marshside, Saltholme and many others. Other clients include many private landowners, Natural England, Environment Agency, Carillion, Tweed Forum and several county Wildlife Trusts.

Funding

Wet features created by the ditcher may be eligible to receive capital funding through agri-environment schemes.

Experience shows that in most cases agri-environment funding will cover the costs of the work. You should discuss any plans at an early stage with the appropriate body for your area, to ensure scheme compliance and available funding.