HARMONISED NUTRIENT LOAD REDUCTION APPROACHES WITHIN SAFE ECOLOGICAL BOUNDARIES IN CATCHMENTS LOCATED IN NW EU

Project Information

NEW-HARMONICA

Grant agreement ID: 101060329

DOI

10.3030/101060329

Project closed

EC signature date 3 June 2022

Start date 1 September 2022

End date 31 August 2025

Funded under

• Food, Bioeconomy Natural Resources, Agriculture and Environment

Total cost

€ 1 000 000,00

EU contribution

€ 1 000 000,00

Coordinated by

STICHTING WAGENINGEN RESEARCH
Netherlands

Periodic Reporting for period 2 - NEW-HARMONICA (HARMONISED NUTRIENT LOAD REDUCTION APPROACHES WITHIN SAFE ECOLOGICAL BOUNDARIES IN CATCHMENTS LOCATED IN NW EU)

Reporting period: 2024-03-01 to 2025-08-31

Summary of the context and overall objectives of the project

In 2015, the ecological status of 75-90% of surface waters in NW Europe was reported to be less than good. Diffuse pollution with nitrogen (N) and phosphorus (P) from agriculture, together with point sources of N and P pollution from wastewater plants and industry, are a major cause of this failure to achieve good ecological status. Climate change is likely to exacerbate the pollution risk.

Clearly, there is a huge challenge to implement effective mitigation measures to reduce nutrient loadings to air and water to meet desired environmental targets against the background of a changing climate. The synergies and tradeoffs between management actions to mitigate climate change and those to mitigate N and P pollution need to be clarified to develop effective local, regional and national policies. Governance arrangements to implement and monitor the necessary actions need to be better integrated, requiring a consistent and coherent set of environmental indicators.

The overall objective of NEW-HARMONICA is to assess and codevelop a harmonised systemic approach to prioritizing an effective suite of N and P pollution mitigation measures and indicators to meet local to regional environmental targets. To achieve this objective, an experienced NEW-HARMONICA consortium (4 partners from 3 countries) with complementary expertise, skills and networks will work on 4 N and P-polluted cross-border river basins in NW Europe. All partners are involved in an established NW Europe Policy-Science Working Group (PSWG) who together with local catchment stakeholders play a central role in NEW-HARMONICA.

NEW-HARMONICA’s approach is based on a combination of technical assessments, including quantification of N and P flows and load-reduction targets in the study catchments, assessments of governance arrangements, and policy support for the co-development of harmonised environmental policies, based on a strong evidence base and interactions with the PSWG and local stakeholders.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

A key achievement was the development and application of Load Reduction Targets (LRTs), which quantify how much nutrient reduction is needed to meet ecological standards. These were calculated using harmonised methodologies and allocated across sectors using the Polluter Pays Principle, enabling fair and transparent responsibility-sharing. The project applied Material Flow Analysis (MFA) and advanced emission modelling to quantify nutrient stocks and flows from agriculture, wastewater, and food systems. This provided a robust baseline for evaluating the effectiveness of Best Management Practices (BMPs), which were tested under current and future climate scenarios. Results showed that no single measure is sufficient—combinations of BMPs tailored to local conditions are essential. Institutional analysis revealed that fragmented governance, unclear responsibilities, and weak enforcement are major barriers to effective nutrient management. The project proposed inter-sectoral governance models and policy tools to improve coordination, transparency, and stakeholder engagement.
Climate change was found to exacerbate nutrient losses, making adaptive strategies critical. The project highlighted the need to integrate climate resilience into both technical measures and governance frameworks.
Through extensive stakeholder engagement, including the Policy Science Working Group, the project ensured that scientific findings were translated into actionable policy recommendations. These were disseminated via policy briefs, workshops, and a dedicated website.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The NEW Harmonica project delivered a harmonised, science-based framework to reduce nitrogen (N) and phosphorus (P) pollution across four Northwest European catchments. It addressed the urgent need for integrated nutrient management in the context of climate change, biodiversity loss, and fragmented governance. Key impacts include:

* Harmonised Load Reduction Targets (LRTs) were developed and applied, enabling fair allocation of nutrient reduction responsibilities across sectors using the Polluter Pays Principle.
* Material Flow Analysis (MFA) and advanced emission modelling provided robust, catchment-scale insights into nutrient flows and pollution sources.
* Best Management Practices (BMPs) were identified, evaluated, and modelled under future climate scenarios, showing that tailored, multi-measure strategies are essential.
* Governance analysis revealed institutional barriers and proposed inter-sectoral models to improve coordination, transparency, and policy effectiveness.
* Climate resilience was integrated into all aspects of the project, highlighting the need for adaptive strategies to maintain water quality under changing conditions.
* Policy recommendations were co-developed with stakeholders and communicated through briefs, workshops, and a dedicated platform, supporting EU-wide implementation of zero-pollution goals.

The project’s outcomes contribute directly to the European Green Deal and Zero Pollution Action Plan, offering a replicable model for sustainable nutrient governance across Europe.