To underpin regular use of integrated economic and health modeling in impact assessments and socio-economic analysis by public authorities, the MARCHES project aims to advance methodological rigor and consistency in accounting for the welfare economic health costs of air pollution and drinking water nitrate, based on systematic reviews of health effects, and by extending the consensus on established approaches on premature mortality with disability-adjustment of the associated morbidity burdens, while developing European-wide exposure modeling for integrated assessment. Based on expert and stakeholder consultations, the project will provide guidelines and unit prices for an accounting approach that can be applied routinely by EU and national authorities, subject to data availability and policy scenarios. This will be demonstrated in case studies with public authorities in five Member States (CZ; DK; EE; ES; SE) and in one west-Balkan country (XK).