Rural Roadwater Rescue : A transnational strategy extending the role of roads to support rural water systems.

RRR is a project co-funded by European Union (Interreg North-West Europe program) that aims to demonstrates how roads/highways can transform from mono to multifunctional: How they can be technically turned into temporary water reservoirs for runoff water (next to/under the road), while being compliant with the legal regulations for infrastructure and water quality.


Climate change causes an imbalance between water supply by rivers and rainfall and the urgent demands from various users. In short periods, extreme weather events provide water surplus, whereas increasingly longer dry periods face water shortages. Existing systems of storage are not sufficient.

Roads and highways are crossing the North-West Europe (NWE) territory abundantly. They usually drain the runoff water from rainfall events swiftly to canals/rivers, whereas local stakeholders would urgently need this surplus water. RRR will demonstrate an actionable strategy how to save, treat (clean) and locally distribute water through transformation of existing roads/highways. The strategy will comprise an integrated, multi-stakeholders and cross-sectoral methodology. It will be inspired by two use cases (BE: Heverlee, NL: Oirschot/Kloosters) to be comprehensible.

Contexte, enjeux de société

Climate change causes a greater demand for water in dry periods, especially in NWE's rural areas with agriculture, valuable nature areas and smaller villages/towns. In short periods intense rainfall causes a temporary water surplus. Demand and surplus differ in time and place. A solution to temporarily collect and distribute water on site is lacking, as water surplus is swiftly drained through streams/canals. This decreases its ability to infiltrate and replenish the groundwater (the main water source in NWE: ±75%) and its use by local communities. Also, surface runoff water from roads is polluted, causing a decrease of water quality.

On the demand side, the users of water are also facing severe challenges, due to climate change and decreasing groundwater levels. Stakeholders (a.o. farmers, SMEs, businesses and citizens) are negatively affected by this water imbalance, sinking groundwater levels and water pollution. Distribution is a complicated local challenge. The profiles of different user groups are place-based sets of different needs. Seasonal demand patterns must be managed to balance out water scarcity, ensure water quality, but a comprehensively applicable, yet place-based approach is missing.

Transnational cooperation will create synergies to jointly develop and disseminate a comprehensive strategy, thereby lowering the implementation barriers through development of solutions applicable in the different regulatory frameworks and to build a strong learning network to jointly pursue implementation for those cross-sectoral, integrated approaches.


Objectifs, problématique scientifique

The project enables rural NWE regions to achieve climate resilient water management by developing a transnational, applicable strategy for "Climate Adaptive Water Hubs" as a comprehensive blueprint for rescuing or valuing runoff water from roads/highways. This includes collection, treatment and distribution.
Sub-objectives are:
- Deepen learning/cooperation for implementable action in different locations and regulatory frameworks
- Understanding local context, demand profiles, interaction approaches

Démarche, étapes

RRR will build a transnational cooperation network that will strategise a methodology how the monofunctional road can be innovatively transformed to serve two parallel functions: While maintaining road safety (e.g. defer surplus water), temporary water storage (beneath or next to the road) will be realised through adapted design or redesign. The project will elaborate a joint and participative strategy how to distribute the stored water on site. The draining of surplus water into canals will be replaced by an effective response to the user demands for water in sufficient water quality on site. Two exemplary sites will ensure practicability of the approach.

The team will elaborate solutions that will go beyond existing solutions in various aspects (integration, multisecorality, comprehensiveness) and will support:
1) road and highway authorities to: 

  • be guided to tackle the cost intensive transformation: adapt/extent construction of roads/highways;
  • find approaches to collect/clean polluted runoff water on site and prepare it for local use;
  • set a new benchmark for road / highway construction.

2) local users in rural areas (farmers, public services, businesses, industry, households..) to distribute /use water directly, to infiltrate or let it infiltrate and replenish groundwater

3) regional decision-makers to replicate adaptation of infrastructures to "Climate Adaptive Water Hubs" (CAWH)=climate resilient local area of collection, treatment and distribution of water, co-created with the local community).

The project elaborates an actionable strategy that provides answers on two levels, to guide replicators:

  • Integration of technical solutions: water collection, storage, treatment in compliance with regulatory frameworks ;
  • How to meet local user demands: Guidance to identify needs/and participative decision-making with local stakeholders.
Apport spécifique du Cerema

Cerema will contribute to the project by providing its opinions on activites and by providing expertise on the use of non-conventional water (including rainwater) in appropriate contexts and uses.
Cerema will also share its progress on the assessment of water demand and supply at the scale of a territory.

In more detail, Cerema will contribute as follows:

  • share it's experience and expertise on runoff management in France concerning water basins and contribute to the report. The Cerema will produce a "bibliographic synthesis" from several project in which the Cerema has been involved and related to site description/ runoff water pollution / water treatment (Roulepur, Traffipollu, study on pollution runoff water for french environnement Ministry).
  • Contribution concerning French national requirements for the report, by interviewing some french experts regarding non-potable use and/or interview of some potential non-potable water users.
  • Presentation of works done in France on road pollutants and quality problems encountered on French highways.

Partners in this RRR project who together develop a transnational strategy extending the role of roads to support rural water systems:

Rijkswaterstaat (lead partner), Corporatie KloosterslandVlaamse Milieumaatschappij  (VMM), IMEC VlaanderenCeremaTZW. 

Défi R&I
Territoires et ville durables
Année AAP

RRR : Rural Roadwater Rescue

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