Guest Column | November 10, 2017

Advancing Alternative Supplies With Sensor Technology

By Brent Alspach

Advancing_Alternative

New water brings new challenges, such as overcoming heightened regulatory standards and consumer wariness. To ensure water quality and quell concerns, utilities moving toward alternative water sources might also consider updating their monitoring technology.

Water utilities are increasingly employing alternative sources of supply to meet demand induced by population growth, drought, and even threats to the quality of their existing sources. Such alternative sources may include seawater, recycled wastewater, brackish groundwater, and stormwater, among others. Given the typically poorer quality of these alternative sources relative to more conventional supplies, the benchmarks for treatment, public health protection, regulatory compliance, and public acceptance are more challenging to achieve.

Adopting An Innovation Mindset
Despite the challenges presented by these alternative sources, the need to overcome them and bolster long-term water supply portfolio sustainability is prompting unprecedented innovation in the water treatment industry. Although the need to innovate in order to meet these challenges is born of necessity, adopting an innovation mindset that permeates every aspect of a utility’s culture will yield a significant return on investment that transcends any one application.

For those utilities expanding into the use of alternative supplies, the intersection of an innovative culture and water quality and treatment challenges is most acute in the development of new instrumentation and sensor technology.

Sensor Technology: Where Challenge And Innovation Meet
For those utilities expanding into the use of alternative supplies, the intersection of an innovative culture and water quality and treatment challenges is most acute in the development of new instrumentation and sensor technology. Historically, the water industry has been known for its conservative posture, appropriately reluctant to embrace new processes and technologies over the “tried-and-true” mainstays that have successfully protected public health. However, particularly for new sensor and monitoring technology, innovation and the protection of public health are far from mutually exclusive concepts.

Because alternative sources present many of the new water quality and treatment challenges that are driving sensor innovation, utilities that are already treating these supplies represent an ideal proving ground for new technology. Examples of such sensor technology advances may include more effective pathogen detection, online monitoring and detection of emerging contaminants (e.g., pharmaceuticals and personal care products), and/or advanced detection of important water quality metrics yet to be identified.

Although new advanced sensors may cost more than previous generation technology, the potential for optimization and reduced analytical costs may offset the initial expense.

It is not necessary that utilities risk switching existing sensors and water quality monitoring instrumentation with new and unproven devices but, rather, that they accommodate testing these new devices in parallel. With an awareness of this important potential, forward-thinking utilities may allocate a small area within the treatment plant dedicated to such testing, pre-outfitted with safety features, sample lines, electrical connections, and the availability of internet connectivity for remote access.

Moreover, the utility’s organization can plan ahead to commit a small amount of each operator’s time to support applied research and development in assisting with such testing. In this way, the sensor technology supplier experiences support at the test site, the operators enjoy the opportunity for continuous learning, and the organization maintains a smart operational staff that is perpetually at the leading edge of new advancements in water quality monitoring: a win-win-win scenario.

Although the landscape of utility innovation extends far beyond water quality monitoring, improved sensor technology is one important area in which utilities can make an important contribution to the advancement of the industry generally and to the use of alternative supplies specifically.

The Benefits Of Sensor Advancements
The entire industry gains from this proactive and progressive approach to testing new technologies, as it not only generates useful data to enhance the institutional knowledge of alternative source treatment, but also demonstrates the efficacy of new sensor technology in operational plants, thus expediting the widespread adoption of the most successful advancements. Specific benefits include the following:

  • Increased response time — Sensors that collect and analyze samples more rapidly provide the situational awareness needed to manage the unknowns of potentially variable sources of supply. For example, in potable reuse applications, unanticipated and problematic upstream waste discharges could potentially pass through the wastewater treatment process to the downstream advanced potable water treatment plant. Rapid detection of these discharges enables more expedited responses.
  • Improved treatment — The detailed data provided by innovative sensor technology can be used to optimize the advanced processes that are commonly utilized to treat alternative supplies. Next-generation sensors may also enhance automation and bolster treatment plant safety.
  • Reduced cost — Although new advanced sensors may cost more than previous-generation technology, the potential for optimization and reduced analytical costs may offset the initial expense. Moreover, improved water quality monitoring also may yield economic benefits in terms of avoided costs of plant upsets.
  • Better regulations — Additional real-time data that is both more accurate and more precise will likewise enable regulations to be directly related to specific water quality parameters and less based on inferential metrics of treatment process performance. This is particularly true for pathogens; because precise, online, and real-time monitoring technology does not yet exist, the current regulatory paradigm predicates compliance on surrogate parameters that suggest, but do not guarantee, sufficient levels of pathogen reduction.
  • Enhanced public health — More precise, accurate, and comprehensive water quality monitoring conducted at frequencies continually closer to real time help facilitate the level of public health protection necessitated by the use of alternative, poorer-quality sources.
  • Heightened public acceptance — The ability of improved water quality monitoring to demonstrate that the potable supplies delivered to the tap are of the highest quality can engender the public trust that is essential for the use of alternative water sources.

Leaders Of Innovation
Although the landscape of utility innovation extends far beyond water quality monitoring, improved sensor technology is one important area in which utilities can make an important contribution to the advancement of the industry generally and to the use of alternative supplies specifically. And while many utilities may be passively willing to test new monitoring instrumentation, those organizations that create and foster a culture of innovation will actively seek opportunities to engage with equipment manufacturers who are pioneering cutting edge advancements, helping to forge the industry’s future.

Numerous sensors help monitor the desalination of 50 MGD of seawater at the Claude “Bud” Lewis Desalination plant in Carlsbad, CA, a project Arcadis helped design.

About The Author
Brent Alspach is a principal environmental engineer and the Director of Applied Research for Arcadis. He also serves as a Trustee for the American Water Works Association (AWWA) and as president of the American Membrane Technology Association (AMTA).