Sandy beaches are one of the most common ecosystems in the coastal zone, being unique habitats for a great diversity of marine plants and animals. In addition to their natural value, beaches are places where the local population can enjoy a wide range of leisure activities. These activities contribute to the well-being and quality of life of those who practice them.
The most common activities are bathing and sunbathing, with the practice of sports becoming increasingly popular, not only in the water (swimming, surfing, windsurfing, scuba diving, etc.), but also on the sand (walking, running, football, volleyball, yoga, etc.). Beaches, especially urban ones, are also used to host social and cultural activities such as local festivals, municipal celebrations, music concerts, film screenings, etc. The development of all these activities undoubtedly supports and stimulates the economic activity of local communities. European islands such as Canary Islands, Azores and Madera archipelagos, due to their geographical and climatic conditions as well as their natural attractions, particularly the beaches, have become one of the most important tourist destinations in Europe, turning into the main source of income for many of their regions.
Beaches are a much sought-after tourist product throughout the world, with sandy beaches being the most popular for the various recreational activities already mentioned. One of the main criteria for bathers when choosing a beach is its environmental quality, either by observing the cleanliness of the sand and water, as well as by consulting the results of microbiological analyses of the bathing water, one of the few available indicators of their sanitary and environmental status.
Other criteria, such as proximity, available services, information and environmental management, which are included in the Blue Flag programme (an award given at the request of the local authority), are aspects that are increasingly taken into account by bathers, and in many cases are an element of confidence and safety when bathing.
Within the framework of the ABACO project (Improvement of Bathing and Coastal Water Quality in Macaronesia MAC2/4.6c/324), the Canary Islands Institute of Technology’s Water Department has published the document “Technical and health guidelines for beach sands cleaning”. This guide comprehensively addresses the key regulatory, sanitary, and technical aspects related to the good condition and cleaning practices of beach sand.
Topics covered include the presence of microorganisms in the sand and the sanitary criteria adopted by the World Health Organization (WHO). In 2003 the WHO Guidelines for Safe Recreational Water Environments highlighted that sand could act as a reservoir and vector for infections. The most recent WHO guidelines edition, from 2021, includes intestinal enterococci (60 ufc/g) as microbiological quality standards for sand. It also presents the microbiological controls proposed by the Portuguese Blue Flag Programme, which also include E. coli and filamentous fungi.
The practices carried out by municipal authorities, both in the management of beaches through monitoring and enforcement of regulations on permitted uses, as well as cleaning and waste collection processes, are key to maintaining beaches and bathing areas in hygienic and sanitary conditions suitable for safe bathing. So, another very important aspect covered in the Canary Islands Institute of Technology (ITC) Guide is the presence of litter in beach sand, its type and particle size. Various equipment or technologies available on the market for the efficient removal of litter are also suggested. It is an informative document with a practical focus, primarily aimed at technical personnel responsible for beach management.
The main source of pollution of bathing or coastal waters in islands is the discharge of wastewater. Most of the volume discharged is treated wastewater (treated according 91/271 CEE Directive standards), which is discharged to the coast through submarine outfalls. In exceptional circumstances, such as heavy rainfall or pumping failure of the sewerage network, wastewater is discharged into coastal waters from the wastewater pumping stations (WWPS) located in costal settlements.
From an environmental and health point of view, these discharges represent a diffuse pressure on the bathing areas and also on the coastal waters. This is due to the physico-chemical (high concentration of nutrients, organic matter, litter, etc.) and microbiological characteristics of the effluent, as well as to the different uses and levels of protection of the coastal areas where these discharges occur, such as protected areas, bathing zones, aquaculture, seawater abstraction for desalination for human consumption, etc.
For this reason, wastewater pumping stations in coastal areas must be designed or upgraded not only with technical, hydraulic, electrical, and other criteria to ensure their proper functioning within an integrated wastewater management system, but also by considering the additional environmental factors. To asses this issue, and wthin the ABACO project, the document “Environmental considerations for wastewater pumping stations design in coastal areas” has also been published by ITC.
The health and environmental concerns associated with this type of discharge have recently led to a series of modifications in the regulations governing urban wastewater treatment. Thus, the forthcoming revision of wastewater Directive 91/271/EC, which will be published soon, addresses the problem of pollution caused by so-called stormwater overflows and introduces a new obligation to control the pollution caused by these discharges and to establish integrated urban wastewater management plans at the local level to reduce them.
This guide, intended for sewer managers, local or regional water cycle administrations and technicians related, and operating sanitation networks and discharge management, presents essential elements, several technical requirements and commercially available technologies, to improve the quality of discharged/overflowed wastewater. In particularly, treatments/technologies for solid wastes and micro litter removal are considered, in accordance with current and future marine environmental national or regional quality standards and objectives according to the Water Framework Directive and the Framework Strategy Directive.
Both guides are available in Spanish and Portuguese at the following link: https://proyectoabaco.itccanarias.org/es/publicaciones.
The guides have been developed as part of the ABACO project, which focused on assessing, improving, preserving, enhancing, and promoting the bathing and coastal waters of Macaronesia. The project aimed to conserve natural resources while fostering tourism. ABACO: Improvement of Bathing and Coastal Water Quality in Macaronesia (MAC2/4.6c/324), was co-funded by the INTERREG V-A Spain-Portugal MAC (Madeira-Azores-Canaries) 2014-2020 Cooperation Programme.
