Futureproof peat meadow polder

We reduce the soil subsidence and the production of carbon dioxide by applying innovative sub-irrigation systems to the whole polder. It involves innovative ways of water management and land use in combination with sub-irrigation, to decrease the effect of climate change and water demand for sub-irrigation, to reduce emission of carbon dioxide (for about 50%) and soil subsidence, and also to improve water quality and biodiversity.
Technology demonstrated in relevant environment.
Representative model or prototype system, which is well beyond that of TRL 5, is tested in a relevant environment. Represents a major step up in a technology’s demonstrated readiness. Examples include testing a prototype in a high-fidelity laboratory environment or in a simulated operational environment.
The innovation has been tested so far for the Lange Weide, a peat meadow area in the Netherlands, which has to deal with a soil subsidence of about one centimetre a year and high emissions of carbon dioxide (12 – 25 t CO2 /ha/year). There has been a variety of trials with sub-irrigation systems in different peat meadow areas. Sub-irrigation is used by some farmers, so this technique is at TRL 8 or 9. The scale on which it is applied and the combination with a variable ditch water level is new.

How does it work?

With sub-irrigation systems (drainage pipes under the water level of the ditches) water is infiltrated in the soil of the peat meadows and helps to prevent low ground water levels in dry periods. This reduces the oxidation of the organic peat soil. By no longer applying a fixed ditch water level, this effect can be increased and it makes it possible to store more water in the area in periods of heavy rainfall. Redesign of the profile of the ditches increases biodiversity and the possibility to store water. Additional measurements are considered.