Laukka, Vuokko; Kallio, Johanna; Herrmann, Inga; Malila, Riikka; Nilivaara, Ritva; Heiderscheidt, Elisangela
(Finnish Environment Institute SYKE, 2022)
Reports of the Finnish Environment Institute 8/2022
Wastewaters from properties outside centralized sewer networks are a significant source of diffuse pollution and can have a considerable impact on the quality and usability of local water sources if not well managed. Furthermore, sanitation-related regulations, strategies, and implementation have broad socio-economic impacts. This study describes the governance of on-site sanitation in Finland, Sweden, and Norway based on information gathered via literature review as well as a compilation of documentation and statements from project team members with years of experience in the sector and interviews with representatives of stakeholders. It presents a comparison among the three countries, highlighting the key similarities and differences in governance principles, implementation strategies, regulatory framework, stakeholders’ roles and responsibilities, main challenges, and good practices.
Altogether, about three million inhabitants live outside the centralized sewer network in Finland, Sweden, and Norway, representing about 13 percent of their combined population. Furthermore, about half a million leisure homes exist in each country, with the majority situated outside centralized sewer network areas. To mitigate the environmental pressures from non-connected areas, Finland, Sweden, and Norway, have introduced national regulatory frameworks. Besides setting treatment requirements for on-site sanitation systems, these frameworks enable the clarification of the roles and responsibilities of various stakeholders and establish a fluent permit procedure. However, non-compliance issues hinder the implementation of regulations in all three countries. Despite support mechanisms, such as guidance efforts and information sharing, a significant number of properties still lack an adequate treatment system for domestic wastewater. In this study, the main challenges in improving decentralized sanitation management and compliance with current regulations were identified within the following categories: resources, knowledge and competence, public awareness, and data availability.
Various on-site wastewater treatment systems are available, for example, holding tanks, septic tanks, followed by sand filters or infiltration fields, package plants, and dry toilets. Traditionally, however, on-site wastewater treatment in all three countries is still carried out using septic tanks only without secondary treatment. Treatment efficiency provided by septic tanks is not sufficient to reach the requirements where discharge limits apply. In addition, the efficiency of other types of treatment units is also a cause for concern due to reported variations in the systems’ efficacy normally blamed on construction errors or the lack of adequate maintenance or operation. Overall estimates, although sometimes vague, suggest that more than half of the on-site sanitation systems located in areas subject to treatment requirements would not meet the requirements.
Based on the information gathered from Finland, Sweden, and Norway, as well as experiences from other European countries, general recommendations for the governance of on-site sanitation are provided: i) A coherent national regulatory framework is of critical importance as the basis for good governance practices and functioning sanitation service-chain; ii) Implementation of the regulations requires adequate support mechanisms in all levels of implementation (national, regional, and local), for example, risk-based national inspection plan, service-oriented approach to support professional management, multichannel communication, information-sharing and education, systematic data collection, and monetary aid for property owners; iii) Public awareness needs to be increased to strengthen the policy relevance of on-site sanitation; iv) Common platforms are required for presenting the results of various studies, sharing good practices, coworking, and learning from each other both on national and international levels.