IJsselmonde Climate Buffer
In Barendrecht and Albrandswaard, the ARK nature organisation is working on the development of the IJsselmonde climate buffer. The Koedood riverlet is now bordered by a grazed nature reserve and the Zuidpolder has been adapted to allow a flexible water level. The area covers a total of 1000 hectares; its spine is a 10 km long water connection between the Zuiderpark and the Zuidpolder.
Results
The combination of a rising sea level and low river discharges leads to increasingly more salt water seepage. As a result, the area is affected by salinisation.
The current remedy is to pump great volumes of –relatively clean – rainwater from the Oude Maas region into the area as quickly as possible during wet periods. Any additional water needed is taken from the (less clean) Oude Maas. In the long run, the Oude Maas river will unfortunately become saline.
The intended IJsselmonde climate buffer is a robust water system able to accommodate extreme downpours and to store rainwater from the wet periods to be used during dry spells. In addition to a functional climate buffer, this creates room for recreational facilities such as canoe rentals and continuous bicycle routes.
ARK has initiated two model projects within the intended climate buffer: the Barendrecht Zuidpolder and a shore strip along the Koedood riverlet on Albrandswaard municipal ground. The realisation of the Zuidpolder requires detachment of a residential area north of the Zuidpolder. The Zuidpolder will thus become a recreational area and Nature reserve whose flexible water level, featuring a 20 cm fluctuation, can accommodate additional rainwater in a natural manner.
This not only reduces IJsselmonde’s dependence on the increasingly salinising, and not always equally clean, water from the Oude Maas river; it also provides tremendous impetus to the water quality in the area. The relatively dirty water flows from the residential areas, and the river will no longer mix with the clean Zuidpolder water. Furthermore, level fluctuation, in combination with the natural shores to be constructed in the Zuidpolder, will create rich water vegetation. These (water) plants will help purify the water.
The Gaatkensplas and Koedoodseplas lakes situated west of the Zuidpolder are currently flushed continuously on account of water quality issues. This flushing requires large volumes of water from the Oude Maas. The aim is to adapt the lakes in such a manner as to keep up their water quality without major flushing, whilst utilising their storage capacity by linking these lakes to the Zuidpolder and allowing a 20 cm fluctuation in their water levels as well. This will approximately triple the scope of the water system and make it more robust.
The Koedood riverlet used to connect the Nieuwe Maas and the Oude Maas. It is currently no longer connected to the major rivers, and serves as a storage basin for polder water. Wide, environmentally friendly shores will be constructed in the Koedood zone, which will expand the system and consequently make it more robust. The area is currently grazed by several Scottish Highlander cattle; throughout the year they manage the Koedood shores, ensure a more natural development, and provide diversity in the outskirts of Barendrecht. The aim is to expand the area to be grazed, thus creating room for more efficient (grazing) management.
The measures envisaged for the pilot areas will be implemented together by a number of parties, including the municipalities involved, Stadsregio Rotterdam, the City of Rotterdam, the Province of Zuid-Holland, and the Hollandse Delta district water board.
Contact person
Gijs van Zonneveld
ARK Natuurontwikkeling
+31(0)6-5135 8186
gijs.vanzonneveld@ark.eu