Search the EPA Research Database

Project title

Facilitating water table management on carbon rich soils

Primary Funding Agency

Department of Agriculture, Food and the Marine

Co-Funding Organisation(s)

Environmental Protection Agency

Lead Organisation

Teagasc

Lead Applicant

Pat Touhy

Project Abstract

Artificial drainage of carbon-rich soils is a common practice where waterlogging and poor surface condition hinders agronomic production potential. However, soils with high organic matter, when drained, can release carbon dioxide into the atmosphere. There is an estimated 300,000 ha of permanent grassland on drained carbon-rich soils where the carbon pool is vulnerable. There is now recognition of the intrinsic value of such soils to provide other services and functions related to carbon storage and sequestration. Plans to restore these soils will rely on manipulating the water table by removing and blocking existing artificial drainage features in a process described as “rewetting”. While such works are proposed (for 40,000 ha of drained organic grasslands) research to date has focused on potential benefits (assuming significant changes in the hydrologic regime on such sites) and less so on practical implementation. There remains a lack of clear information with regard to where such works would be appropriate and feasible; how, in practice, such works would be carried out, and thereafter, what net benefit these works would provide, what the implications would be for the surrounding landscape and what land use options are feasible after rewetting. REWET seeks to assess the suitability and availability of lands for rewetting, by utilizing existing GIS data and new remotely sensed data, examine practical means of rewetting, by undermining the functionality of open and subsurface drainage channels, assess the effects on hydrology, both at the designated sites and surrounding lands, and quantify associated impacts. This work will provide a deeper understanding of a workable methodology to facilitate rewetting on appropriate placed land parcels, outline the scale of the challenge, quantify its potential benefits and provide a decision support tool to guide best practice methodologies, and quantify full costs and effects associated with such land use changes.

Grant Approved

�250,000.00

Research Hub

Climate Change

Research Theme

n/a

Start Date

01/12/2021

Initial Projected Completion Date

30/11/2025