Water is a valuable resource which needs to be managed more effectively to guarantee its availability for future generations. We tend to believe it is infinite, however its scarcity may vary with time and the predictability of water security is questionable.
The quality and quantity of traditional water supplies are dependent on population growth, urbanisation, industrial expansion, extended droughts, and varying climate conditions. Relying on underground and surface water may just not be enough.
To address the growing demands of water needs and ensure water security, we need to diversify our water sources. Holding a portfolio of sources will help meet future water requirements, safeguard public health, and promote economic and environmental sustainability.
Numerous communities are striving to enhance water conservation efforts and explore fresh approaches to creating sustainable water sources for the future. Consequently, there's a definite requirement to maximize the efficient utilization of our existing water resources to generate and distribute dependable, superior quality water.
A viable option, proven highly feasible (technically and economically) is direct potable reuse (DPR), which converts treated wastewater to drinking water. Utilising advanced treatments, the wastewater can be diverted to a drinking water source and then used directly in the water distribution system.
Communities around the world have examined and are starting to implement direct potable reuse as a means of creating another water source, with many finding that it is a cost effective, safe and sustainable option to augment their drinking water supplies.
Nonetheless, according to the EPA, more than 32 billion gallons of municipal wastewater are processed every day in the U.S. but less than 10% of that is intentionally reused with only a fraction of that used for potable purposes.
What are the necessary steps to move the needle towards direct potable reuse and guarantee its success?
The challenges of water reuse: navigating conflicting interests
In different regulatory environments, that wastewater collection, treatment and discharge are managed and operated by a separate utility from that which provides the potable water to the residents, industrial users and agriculture. This distinction results in varying interest related to water quality and quantity as each utility has its own criteria, guidelines and regulations to adhere to.
To maximise the amount and quality of water that can be recouped out of wastewater, a more centralized, standardized approach to water treatment is needed. Taking the full responsibility over both the wastewater treatment cycle — from primary and secondary through tertiary treatment — and advanced treatment up to DPR standards within a single entity would facilitate improved process management.
This will ultimately lead to the recovery and transformation of more wastewater into drinking water at optimum quantity while ensuring the quality.
Leveraging public-private partnership to drive effective water reuse
Reusing treated wastewater is a circular economy approach with potential benefits for millions of people. However, do not underestimate the complexity of the technology involved in executing direct potable reuse programs. The process consists of multiple stages, involves various treatment solutions, and no two projects are identical.
Furthermore, the successful implementation and expansion of potable reuse initiatives necessitates rigorous, ongoing monitoring of water quality standards. Guidelines and benchmarks must be regularly updated, and process controls must be improved as treatment technologies and strategies advance. Additionally, tailored operator training and certification programs must be followed to meet the demands of each project.
Getting it right without wasting public money and time is a challenge. A public-private partnership approach may be a solution. Public-private partnerships are becoming an increasingly used method to deliver large-scale water infrastructure projects worldwide. Working together, private companies and government entities can combine their strengths to develop, design, finance, and operate new water facilities and wastewater infrastructure projects.
One of the main benefits of a public-private partnership is that it provides a full life cycle cost-effective and efficient solutions, thanks to the expertise of private partner and the resources and regulatory power of public entities.
Public-private partnerships effectively allocate risk among all parties involved, which can lead to the most advanced, robust, and efficient outcomes for the public for the long term. This model has been successfully used to execute large-scale complex projects across the globe and has gained the trust of global financial institutions and lenders.
In addition to project development, public-private partnerships can offer operation and maintenance management services for water treatment plants around the world. This ensures the plants are managed effectively and in compliance with local standards and regulations, assuring the health and safety of employees.
A range of services can be provided, including long-term operation and maintenance services, periodic site inspection, remote plant operation supervision services, and preparation and implementation of maintenance plans.
Why we cannot afford not to reuse
In a recent conference on water solutions, an executive from an inland water authority had no need for water reuse; at least that was the case on paper. With no industry that requires water and a generous yearlong water supply from a nearby river, it seemed like they would be the last candidate for direct potable reuse program.
Nonetheless, they were interested. Water shortage due to droughts and unpredictable weather, upstream pollution and increasing water demands of an ever-growing population are just a few of the reasons that drive this interest. This public official executive, with years of experience in the industry, saw great importance in diversifying the region's water portfolio as a way of risk mitigation. With no access to sea water, the river was the sole source of freshwater. And trusting one source of water is never a good idea.
That executive's voice is not alone. Understanding the importance of creating new water sources along the conservation of existing water sources leads many to realize that reuse is not only inevitable, but also logical. Using every drop twice is the ultimate solution for the huge amounts of wastewater that pour into rivers and seas every day. It makes highlights water recycling as an overall environmental solution that enables the reuse of this water and the diversification of regional water portfolio.
Scaling up water reuse
Looking beyond the comfort zone of developed countries, the scale of the challenge is impossible to miss. According to recent UN reports, as much as 36% of the global population lives in water-scarce areas, water demand is expected to rise to 55% by 2050 amid rapid urbanization, and yet 80% of global wastewater is not adequately treated. In developing countries, wastewater treatment and reuse is critical to boosting economic progress, eradicating poverty and driving sustainable local development.
The economic feasibility of reuse solutions is increasingly seen as a viable option. However, it is a moral obligation to subject developing countries only to processes that have been tried and tested in our own backyard. Thus, as direct potable reuse programs are scaling up in the developed countries, and new regulations around the use of DPR are implemented, this can expand DPR to the rest of the world.
Nonetheless, the challenges of implementing a water project in developing countries and emerging markets must be apprecaited. Those challenges include the lack of necessary infrastructure such as proper sewage collection and water distribution; lack of proper supply of energy, and inability to finance a project, which shall require the involvement of the sovereign government. Such projects need to be utilised following proper regulatory frameworks to safeguard the health of the people.
The success of such reuse projects depends eventually on the formation of well-structured private-public partnerships that can leverage private capital, expertise and experience to accelerate and properly manage such large-scale potable reuse solutions in emerging markets with the cooperation of the relevant public financing institutions.
Direct potable reuse leaders are needed
The implementation of DPR projects is a complex and challenging task that requires strong leadership and a "can do" approach. DPR can help alleviate water scarcity and increase the availability of safe drinking water in areas where water resources are limited. However, DPR projects require significant investment in infrastructure, technology, and regulatory frameworks, as well as public acceptance and support.
Leaders in communities and water authorities who are strong believers of investments for the long term and the future of their community are essential for implementing these projects. Such leaders have the vision, determination, and perseverance to overcome obstacles and see them as opportunities to make progress. They are able to communicate the importance of these projects to stakeholders and the public, navigate the complex and challenging landscape of water resource management, and ensure that safe and sustainable water supplies are available for future generations.