REDUCING HEALTH RISKS

Depending on the type of water (re)use, different water quality requirements are of importance. For instance, drinking water will require higher quality as compared to irrigation water. In general, removal of well-known contaminants, such as disease-causing micro-organisms (pathogens), toxic heavy metals and organic micro-pollutants (e.g., pharmaceuticals) may be needed for healthy re-use. Lately, increasing attention is given to the risks of antibiotic resistance when re-using waste water.

Since the discovery of antibiotics in the late 1920s, human beings have incorporated them to many aspects of our day to day lives. Eventually, antimicrobials found their way into our streams, rivers, lakes and soils which has led to the emergence of antibiotic resistant bacteria. Conventional water treatment technologies are generally not efficient in removing antibiotics and resistant organisms. Antibiotic resistance will receive special attention in our project.

LOTUS^HR offers a unique sequential treatment environment that will make safe reuse possible. This research project will determine which uses are compatible with the produced water qualities and explore further advanced treatment to expand reuse possibilities. By doing so a water treatment scheme can be devised that ensures safe re-usable water.

To ensure that pathogens, heavy metals, organic micro pollutants and antibiotic bacteria are effectively removed from the water during treatment, the focus will lie on water treatment technology development. The magnitude of infection (or illness) will serve as an indicator to determine performance of water treatment technology or define the reuse potential of treated water.

Specific attention will be given to the type of water reuse and the related water quality requirements. The ruse of water is governed by the risk various contaminants through different exposure routes; i.e., the way people come into contact with the water depends on the activity. A health risk assessment will include exposure routes, both for microbial and chemical contaminants, and dose-response relationship.

Risk assessment traditionally is performed using individual contaminants but the focus here is to identify key reference indicators in each contaminant group and adopt a consolidated risk assessment approach for all contaminants. This holistic risk assessment approach will be able to show us what treatment technologies are required to achieve safe reusable water per specific purpose.

Additional, tertiary treatment steps might be required in addition to LOTUS^HR technologies to ensure water safety, technologies that will be explored are advanced oxidation steps, such as ozone or peroxone treatment, electrocoagulation, membrane technologies such as nanofiltration and reverse osmosis, and UV based systems.

Safe reuse of effluent

By developing strict guidelines for water safety and quality, water reuse becomes a reality. Through matching water safety and quality to its intended use, additional treatment steps can be proposed. This makes local treatment and reuse possible which will have a positive effect on the city’s water balance. 

Source of income

Increasing the availability of safe water will immediately reduce the costs related to water shortages, reduce water related health effects and improve commercial activities that rely heavily on water. By locally treating water up to the quality that is needed, societal costs for the production of safe water becomes more balanced.

Knowledge creation & dissemination

Our goal is to create strict water treatment guidelines that match water reuse options to the health and quality requirements of the produced waters. These guidelines can be used by stakeholders and will be applicable for other water reuse projects thereby ensuring safe reusable water in future water projects.