USING THE FORCE OF THE SMART GRID FOR WATER
In 1974—three years before we became aware of the Rebel Alliance—the regulatory Empire enacted the Safe Drinking Water Act (SDWA). The SDWA established a cohesive federal set of standards for water quality delivered to consumers.1 Water utilities were now required to meet water quality standards, defined as Maximum Contaminant Level Goals (MCLGs) and Maximum Contaminant Levels (MCLs), for prescribed constituents prior to delivering water to customers. Our knowledge and understanding of the health effects of constituents and potential contaminants, however, is continually evolving. This means, as water managers, we must continually advance our own operations in order to meet these increasingly stringent regulatory requirements, and do so in an efficient and economical manner.
One driving force for this evolution is the advancement of sensing techniques and laboratory methods. Constituents can now be detected at levels well below the parts per trillion range—the equivalent putting a single drop from an eyedropper in a 4 million gallon water tank. They are also identifying man-made and natural constituents in our water that we had not identified before. And while the SDWA currently regulates 87 primary contaminants2, the Chemical Abstract Service (CAS) Registry contains more than 104 million unique organic and inorganic chemical substances.3
To address these continuing advances in our understanding and detection capabilities, the Environmental Protection Agency (EPA) makes regulatory determinations for at least five potential contaminants every five years.4 These determinations can have substantial impacts to water utilities, particularly as the costs of meeting these new standards fall to the utilities—and ultimately their customers. The last major change to the SDWA, for instance, reduced the MCL for arsenic from 50 parts per billion (ppb) to 10 ppb. In Arizona alone, the capital cost of meeting the new standard was $250 million.
On the horizon for our utilities are EPA’s Stage 2 Disinfectants and Disinfection Byproducts Rule, the Revised Total Coliform Rule, the potential regulation of Chromium VI, perchlorate, N-nitrosodimethylamine (NDMA) and strontium, as well as possible changes to fluoride, lead and copper regulation.
BECOMING THE UTILITY MASTER WITH DATA SYSTEMS
Historically, water and wastewater utilities have lagged the advances in data and analytics that have revolutionized commerce, airlines, financial institutions, political campaigns and a host of other industries. Limited capacity in data acquisition, and the tools necessary to curate and analyze that data have hindered the use of “big data” in water. This is primarily because data remains siloed within the utility, minimizing the overall positive impact those tools can have for the utility—advanced metering infrastructure (AMI) is considered a meter reading technology; leak detection is considered an asset management service; sensors are considered as SCADA elements.
With the right tools, however, we can combine these data systems and achieve the Smart Grid for Water and allow the value propositions to expand dramatically—particularly as it relates to meeting our current and future regulatory challenges. For example:
Stage 2 Disinfectants and Disinfection Byproducts Rule
The current regulation for disinfection byproducts (DBPs) is established under the Stage 2 Disinfectants and Disinfection Byproducts Rule (Stage 2 DBPR), which requires the monitoring and management of a locational running annual average DBP concentration at sites determined by the utility to most likely to generate DBPs. Such an assessment can only be accomplished with an understanding of how water age, residual disinfectant, temperature and naturally occurring organic matter are distributed within the water system.
With temperature, disinfectant and DBP sensors integrated with consumption data, utilities can better understand where areas of increased detention time exist within the distribution system, and identify the potential of increased temperature on DBP formation. Based on these assessments, additional flushing routines and the potential installation of automated flushing valves may be warranted to reduce DBP potential. But more importantly, a utility may be able to avoid significant resource expenditures by demonstrating real-time DBP compliance of their systems.
Disinfection byproducts are generated through the interaction of disinfectants such as chlorine and ozone with naturally occurring organic matter in water sources and their creation is enhanced in areas of high temperature and increased water age.
Revised Total Coliform Rule
The EPA Revised Total Coliform Rule (RTCR), effective 01 April 2016, establishes an MCLG and MCL for E. coli for protection against potential fecal contamination. To meet the terms of the RTCR, a utility must collect coliform samples according to a written sample siting plan and ensure that samples are collected at locations representative of the entire distribution system. In determining the sample site plan, a utility needs to consider:
- Pressure zones;
- Zones upstream and downstream of storage tanks with dedicated inflow and outflow lines (i.e., tanks that do not “float” on the distribution system);
- Areas of the distribution system delivering water from different sources;
- Areas of the distribution system with longer hydraulic retention times; and
- Areas of the distribution system with lower hydraulic pressures.5
Combining AMI data, distributed disinfectant sensors and hydraulic models informs the utility of the spatial quality of water in their distribution systems, identifies areas where transient backflow conditions may exist, isolates conditions where large pressure fluctuations exist, and illuminates other operational or infrastructure defects that could provide a pathway of entry for microbial contamination. This information makes the utility’s sample siting plan more accurate for regulatory purposes, and more useful as an operational management tool. Adding Laboratory Information Management Systems (LIMS) and customer data from Customer Service and Customer Information Systems allows for a comprehensive distribution system monitoring effort.6
GOOD IN THIS ONE, THE FORCE IS
In order to achieve this level of sophistication, utilities require a data infrastructure that provides:
- A landing pad for utility data, allowing the ingestion of raw data from sensors, external data sets, and the output from modelling and decision support systems;
- A means of curation for that data, in time and space; and
- The means to analyze that data into useful information for the utility.
FATHOM represents a singular advance in the provision of data management for water utilities. Through FATHOM, utilities can realize the benefits of highly granular data outside the structural confines of traditional systems. FATHOM democratizes the collection and curation of data, while at the same time providing efficient and economical tools to transform this data to information.
By combining data from sensors and systems, utilities can make quantitative determinations on the quality of water in their distribution systems, understand the quality of water in real-time, plan for potential changes to the regulatory regime and maximize the efficiency of maintenance and capital expenditure budgets.
Meeting the needs of utilities through the adoption of data, algorithms and information is FATHOM’s credo.
May the Force of data be with you in your quest to become a utility master.
1The Safe Drinking Water Act (SDWA) was originally passed by Congress in 1974 to protect public health by regulating the nation’s public drinking water supply. The law was amended in 1986 and 1996.
4EPA has recently published Contaminant Candidate List 3 including 12 microbial contaminants and 106 chemical contaminants (http://water.epa.gov/scitech/drinkingwater/dws/ccl/ccl3.cfm#ccl3)
6Feedback from drinking water consumers is particularly valuable to water suppliers, because it is a “real-time” water quality assessment at no cost to the utility. Additionally, these water quality monitors are located at every point in the distribution system where water is being used at all times (U.S. Army Center for Health Promotion and Preventive Medicine, “USACHPPM TG 284 Drinking Water Consumer Complaints: Indicators from Distribution System Sentinels”, May 2003)