NSWRM Deep Dive


There is a lot of science hidden in our small retention measures. Take a deep breath and explore everything NSWRM has to offer. 


The OPTAIN project is gathering knowledge on the implementation of a set of small size NWRM called “Natural Small Water Retention Measures (NSWRM)” on headwater catchments in the agricultural sector in 14 case studies representing various biogeographical conditions. The modelling and optimization of various combinations of NSWRMs will be at the heart of the project and will be finally transferred in a “Learning Environment” which will provide NSWRM end users with the knowledge created by the project. The aim is to improve the technological readiness of these measures and demonstrate and optimize their benefits on water and nutrient retention, recovery and reuse. But what are NWRM and NSWRM, and what will be done in the project to allow access to these results: this is the focus of this article.


NWRM in practice

In the second cycle of implementation of the Water Framework Directive - WFD (2000/60/EC), it has been recognized that Natural Water Retention Measures (NWRM) could be implemented to a wider extent and contribute significantly more to the achievement of good water status. Further work following this concluded that due to their multi-functionality, NWRM can be placed within the framework of three EU policy areas, namely the water policy, the policy on climate change (because NWRM increase resilience) and the green infrastructure policy (because NWRM are providing ecosystem services and consider nature and biodiversity). A large project aiming at creating a knowledge hub (http://nwrm.eu) was then conducted under the umbrella of the European Commission and produced the conceptual framework, identified a list of 53 NWRM categories and gathered information on more than 130 past projects all over Europe which have implemented one or more of these NWRM categories.

NWRM are defined as follows: “Natural Water Retention Measures (NWRM) are multi-functional measures that aim to protect and manage water resources and address water-related challenges by restoring or maintaining ecosystems as well as natural features and characteristics of water bodies using natural means and processes. Their focus is to enhance, as well as preserve, the water retention capacity of aquifers, soil, and ecosystems with a view to improving their status. NWRM have the potential to provide multiple benefits, including the reduction of risk of floods and droughts, water quality improvement, groundwater recharge and habitat improvement. The application of NWRM supports green infrastructure, improves or preserves the quantitative status of surface water and groundwater bodies and can positively affect the chemical and ecological status of water bodies by restoring or enhancing natural functioning of ecosystems and the services they provide. The preserved or restored ecosystems can contribute both to climate change adaptation and mitigation.” (Source: DGENV, http://nwrm.eu/concept/3857).

Currently there are 53 measure categories in the NWRM catalogue which, for ease of use, have been organized in four geographical sectors (named agriculture, forestry, urban, hydro morphology: this last corresponds to rivers and their surrounding environment). The sectors are referring to the geographical location in which these measures are typically implemented but any measure can be implemented in all parts of the territory, because in general a territory is a mixture of the four main inland use types and frontiers between them are soft. For instance, the frontier between “A02 buffer strips and hedges” and “F01 Forest riparian buffers”, lies mainly on the type of vegetation used, or “U04 Swales”, can be used to manage rainwater or excess water in forest or agriculture territory. The nwrm.eu platform has been developed to provide clear and structured access to knowledge. On the platform, each measure category is described in detail in a dedicated factsheet and linked to a set of case studies which have implemented one or more measures. The factsheets are accessible via the NWRM catalogue as can be seen in the following screenshot (see next page).



Under WFD it has also been recognized that agriculture is a major contributor to the pressures stemming from human activities on freshwater, especially regarding pollution from nutrients and abstraction of water. On the other hand, agriculture is a key actor in landscape management and could make more use of simple NWRMs to reduce its pressures on freshwater ecosystems.

As compared to NWRM, as per the call SFS23-2019 (see link) NSWRM in OPTAIN perspective have a slightly adjusted scope by focusing on:

  • catchments with land occupation mostly of agriculture and forestry categories, covering headwaters,
  • small and simple measures allowing easy implementation,
  • retention, recovery and reuse of water, nutrients and sediments.

This can be translated in short:

For more details see the dedicated article.



NSWRM also go in line with the definition of Sustainable Land Management (SLM) of the World Overview of Conservation Approaches and Technologies (WOCAT) and can thus be linked to the WOCAT SLM Technology Groups. Considering that NSWRM are in fact a specific case of NWRM and go in line with the SLM definition, the use of existing tools from NWRM website and WOCAT are relevant for the OPTAIN project to save time and resources. NSWRM will therefore be firstly documented on the WOCAT Global SLM Database (https://qcat.wocat.net), and then linked to the NWRM website. The resulting knowledge will form the basis of the OPTAIN NSWRM catalogue.

A catalogue of NSWRM

To gather the knowledge collected and created by the project, a catalogue of NSWRM will be developed. It will present each NSWRM considered in the project and all the associated information. The objective is to make qualitative and quantitative information on each specific measure available to all end users, and NSWRM implementers, to allow them to select, design and implement one or more NSWRM on their farm (or territory). The NSWRMs will be integrated in the WOCAT Global SLM Database and linked to the NWRM catalogue.

The catalogue should cover all relevant NWRM categories and include the most relevant measures of each case study. Thus, before starting the individual NSWRM data collection, a step-by-step approach is needed involving all relevant stakeholder groups with the following steps: i) identification of existing or potentially suitable measures, ii) prioritization of measures with a high potential in the local context of the different case studies, iii) selection of a set of 3 to 7 measures per case study, which are relevant for the case studies and the OPTAIN project. Once the NSWRMs are selected, all case study implementers will start to collect data on their individual NSWRMs and document them with the WOCAT questionnaire on SLM Technologies to generate a standardized factsheet of each NSWRM. All entered data on the WOCAT SLM database will then be linked to the NWRM platform. The OPTAIN catalogue will be accessible from both websites as well as through the projects own “Learning Environment” which will include a section dedicated to NSWRM catalogue.

Identification of measures

In the last months, a survey was conducted towards case study leaders of the OPTAIN project to gather the set of measures that are already implemented, planned or intended to be implemented.

After an analysis of the results, we are proud to say that OPTAIN covers already:

-    212 individual NSWRM identified by case studies, distributed in 42 different NWRM categories

-    These 212 NSWRM can be linked to 302 individual SLM practices distributed in 20 technology groups

Some measures are already implemented in the case studies (Existing NWRMs), some are planned to be implemented soon (Planned NWRMs) and some present a good potential to be implemented (Potential NWRMs). In the following two graphs, we selected the NWRM categories and SLM groups which include ten or more NSWRMs.

In OPTAIN, the case studies involve a set of stakeholders, which meet regularly to coordinate the case study implementation in a so called Multi Actor Reference Group (MARG). In a first meeting of the MARG, stakeholders must identify in each case study additional NSWRMs which are suitable for the local context but have not been identified in the first above-mentioned survey. This will again extend the above analyzed list of identified measures. Based on the extended list, each case study is selected together with different stakeholder groups 3 to 7 measures which are relevant for the case study and the OPTAIN project and which will be implemented and investigated in detail in the case study. The measures selected in all case studies should finally represent all relevant NWRM categories of the project and will be included in the OPTAIN catalogue.


Some conclusions of this first step

The analysis of the survey conducted shows that identified OPTAIN measures can be organized in three main groups:

  1. Measures that are already described in the NWRM catalogue.
  2. Agricultural measures which cannot be allocated to the current NWRM categories. Most of these measures which positively affect water use efficiency of the agricultural production (crop rotation, conservation tillage, etc.) or nutrient can be qualified as NWRM either by extension of the catalogue or by embedding them in existing measures with some additional information to be include in the NWRM catalogue,
  3. Measures specifically targeted for OPTAIN (like dual irrigation drainage system) for which the qualification as NWRM/NSWRM must be further discussed and investigated.


Next steps

Once all case studies have selected together with local stakeholders their preferred set of measures, the partners will analyze the situation and identify potential gaps for the OPTAIN project. This will be discussed at the next general assembly in order to assess if it would be possible to select a few additional measures in one or more case studies to allow more complete coverage of all possible measures in the project.

Before the end of the year 2021, the case studies will finalize the selection of the NSWRM they will investigate in more depth and document each measure with the questionnaire on SLM Technologies. The link between WOCAT SLM and NWRM will be investigated, as well as addition of new NWRM in the NWRM catalogue. We expect the first version of the catalogue to be available in the first half of 2022. Close interaction with the partners developing the Learning Environment will occur during this period to allow develop the catalogue infrastructure and connectors for a smooth integration of the NSWRM catalogue in the Learning Environment.

Autors: Dr. Tatenda Lemann and Benoit Fribourg-Blanc