Eco-hydrology and Peat Investigation - South Cumbria Raised Bogs

Natural England are grounded in science, and it is imperative that our evidence base is strong and robust in order to restore nature. The sites of interest in this study are The Duddon Mosses Site of Special Scientific Interest (SSSI), part of the Duddon Mosses Special Area of Conservation (SAC), Rusland Valley Mosses SSSI and Nichols Moss SSSI (Part of Witherslack Mosses SAC) in south Cumbria. These Internationally and nationally important lowland raised mires are found on the floors of the Rusland and Duddon valleys and the valley of the River Winster. The Duddon Mosses lie in a wide glacial valley stretching from the Furness fells to the Duddon Estuary. The underlying solid geology is Coniston Grits, part of the Silurian Ludlow series. A rise in sea level 5000 years ago deposited a mantle of estuarine clay on the coastal plain of South Cumbria. In this area the clay is over 7 metres. The narrow Rusland valley is oriented North-South and situated due South of central Lakeland fells. It is enclosed by the low, rugged, largely wooded Furness fells. The Rusland Valleys and Fells sit entirely within an area of relatively soft Silurian Slates. Nichols Moss is one of the three raised bogs forming part of the Witherslack mosses complex of fragmented wetland, together they form the largest remnants of a formerly extensive wetland on the coastal plain of the River Kent. The area is underlain by estuarine clay of low permeability, separating the peat from solid geology (Silurian with Carboniferous Limestone) below. Estuarine raised bog originally covered much of the low lying coastal plain and valleys of South Cumbria. These three study sites represent the remnant raised bog domes of a once extensive coastal fringe wetland landscape. The original hydrological environment of the valleys and plains has been significantly modified over centuries, through land reclamation and deliberate drainage. More recently, transport infrastructure and flood banks have largely divorced the floodplain wetlands from rivers and estuaries. This has resulted on a significantly fragmented system of raised bog surrounded by peatland supporting agricultural grassland for grazing livestock. The focus of this study are the peatland areas surrounding the Duddon Mosses SSSI, Rusland Valley Mosses SSSI and Nichols Moss SSSI. The study area includes the hydrological environment, including historical, that supplies and supports these complex wetland sites. The historical, current and future, in response to climate change, hydrological environment also forms part of the study. The field work is largely on private land, permission for access will be arranged by Natural England prior to commencement of the contract. Private land is not to be accessed for the purpose of this tender bid, unless viewing from public road or public Right of Way.

Objectives The purpose of this project is to review the ecohydrological status of the three SSSI’s, with a focus on the peat deposits in the surrounding landscape and the potential for the restoration of peat-forming conditions in general, and in the context of ombrotrophic bog. Investigation of the land beyond the SSSI boundary is of primary interest to this study, providing insight into the naturalised state of the historic peatland system hydrology and an account of the degree and effect of modifications over time.