Bourne Valley Water Level Management Plan (WLMP)

The concept of Water Level Management Plans was introduced in 1991 by MAFF (now Defra) and requires that plans should be produced for areas where water levels are managed.  

Priority is given to Sites of Special Scientific Interest (SSSIs) with the main requirement that "ideally, plans should be prepared for all areas which have a conservation interest where the control of water levels is important to the maintenance or rehabilitation of that interest"

The Defra WLMP database currently identifies 476 SSSIs as requiring Water Level Management Plans, one of which is the Bourne Valley SSSI.

A pre-plan study was funded by Defra.  To produce the Bourne Valley WLMP the Partnership's Project Officer worked with English Nature, local botanist & consulting scientist Robin M Walls, and environmental quality consultant Robert Aquilina.

Related Studies

Spreadsheet Model of the Bourne Stream in the Bourne Valley SSSI

An in-depth study into the sources and hydrology of the Bourne Stream has been carried out for the WLMP by Robin Walls. 

One output of that is a spreadsheet model of the stream into which a flood pulse measured at the Branksome Wood Road gauging weir (October 2003) was input to test the dynamic response (excel file, 800kb).

The results are discussed in Appendix III of the WLMP.

The model is interactive; the effect of adding new information or changing the value of a feature (the width of a weir, for instance) can quickly and easily be seen in the graphic representation(s). 

The model is not fully tested, not all assumptions are necessarily valid, and it is for illustrative purposes only; neither BSP nor Robin Walls accepts responsibility for its use outside of the Partnership.  Constructive comments and suggested improvements welcome!

Ecological Survey 2005

In August 2005 Robert Aquilina carried out an ecological survey of the stream in the Bourne Valley SSSI.

He found that the biological assessment graded the Bourne Stream as High with a RIVPACS band B (Good). The environmental quality has improved over the last ten years compared with two previous surveys. Three Nationally Notable species of beetle were found in the valley.

• Download the full survey report (PDF 460kb).