Mark Reiner, PhD, PE
Defining ‘Reliable’ Infrastructure as a Key Performance Metric for City Resilience
While there are numerous frameworks assisting cities in establishing sustainability and resilience goals, I have yet to find one that adequately, or at all, addresses the significance of benchmarking service levels of basic infrastructure services. That is, defining the reliability of energy, water, and sanitation services as a critical step towards creating city resilience. Even in the ‘smart city’ discussions, it is rare to include “…efficient service delivery of basic services and infrastructure such as public transportation, water supply and drainage, telecommunication and other utilities.” But what happens when the ‘efficient delivery of basic services’ are not maintained? When the citizens and businesses in a city view infrastructure as unreliable, a major socioeconomic shift occurs that needs further definition. Consider the juxtaposition of the following examples from the United States with India.
Energy: In the United States, my energy provider is Xcel Energy and they report two key performance indicators (KPIs) each year: 1) the System Average Interruption Duration Index (SAIDI) – reported in the average number of minutes a typical customer was without power in a year, and 2) the System Average Interruption Frequency Index (SAIFI) measured as the average number of power outages experienced by an average customer over a year. Last year was typical, where the SAIDI equaled 95.59 minutes and the SAIFI equaled 0.99. As such, the reliability of our electricity prevents the need for diesel generators as back-up sources (some buildings have them, but are rarely used). Compare these KPIs of reliability to the World Bank Group’s Energy Sector Management Assistance Program (ESMAP) tiers of energy performance. An energy system can achieve the highest level (Tier 5) by providing electricity to a customer a minimum of 23 hours per day. This means, that a provider could be classified as a Tier 5 supplier even if they experience one outage per day and loss of service for 59 minutes per day. Or, in other words, a SAIDI of 21,535 minutes per year and a SAIFI of 365 outages per year. Tier 4, the next highest level, allows up to 8 hours per day without electricity. At what point do end-users resort to purchasing and utilizing back-up sources? Already Indian manufacturers lead the world with over 40% of firms owning or sharing private generators and have attributed approximately 6.5% loss of their annual sales to unreliable energy.
Water: While there are now global concerns with water quality from municipal services, these concerns can be generally categorized as either virus or metal contamination. The difference being the reliability of the system to deliver water at all. For example, Flint, Michigan made global news for having high levels of lead in the water system. This is a result of aging infrastructure and poor operational decisions. And, while there is some concern for water quality in the United States, the concern is mostly on metals. Even then, most cities show that household water quality is very good to excellent. The shift to viruses being the main concern in water quality is when the water system is not pressurized 24/7. A service level benchmarking (SLB) program carried out by the Government of India’s Ministry of Urban Development (MoUD) in 2006 in 28 cities, found the average duration of water supply was 3.3 h per day, with a range from one hour every three days to 18 h per day. When water lines are not pressurized on a reliable basis, it is relatively easy for contaminated groundwater, or stormwater runoff, to contaminate water mains. And, once the pressure is restored, the contaminated water is pushed to homes and businesses – creating a new paradigm. That is, the water distribution paradigm shifts from: treat -> distribute -> consume to treat -> distribute -> pump -> store -> re-treat -> consume. These three extra steps require that the end-user not only purchase their own personal infrastructure to remediate municipal services, but also consume more energy. This represents a major loss in the scale of economy for supplying basic services.
Sanitation: Finally, how are cities defining reliability with regards to the municipal solid waste (MSW) system? In my lifetime, I do not recall garbage service ever missing a pick-up schedule, other than a day or two, due to inclement weather or holidays. What happens to a city where the MSW system is not reliable, or too costly for many of the citizens? The most immediate response by citizens would be to burn the waste. In cities with reliable services, this would of course be met by immediate citations and monetary penalties. But, when a city’s MSW system is chronically unreliable, the burning of MSW in the streets, or even the Bhalswa landfill in Delhi, becomes a fact of life. The higher levels of localized air pollution, such as fine particulate matter (PM2.5) and ozone (O3), lead to respiratory disease. While none can escape the impacts of outdoor air pollution, the wealthier residents and businesses again will purchase additional infrastructure that requires additional energy, i.e. air filters, in order to alleviate the indoor air pollution levels.
When basic services are unreliable in a city, citizens and businesses have to compensate for this unreliability by purchasing personal systems—referred to as remedial secondary infrastructure (RSI). In developing nations where the occurrence of unreliable service, or no services at all, is high, there is a wide range of RSI already purchased as part of a massive private infrastructure system. Maintaining RSI though leads to a chronic stress of daily maintenance and cost—the range of these costs depends on the quality of the RSI desired by the household. While RSI is not as evident in the United States, we will see a continued deterioration of our basic services and need to add more proactive KPIs to a city resilience plan that prevents the need for RSI. In developing cities where RSI is prevalent, two suggestions for better incorporating infrastructure reliability into a comprehensive city resilience plan are: 1) SLBs from the utility service point of view, and 2) mapping the type of RSI being purchased by the range of socioeconomic groups in a city that can better determine the final unit price for each sector (e.g., $USD/kWh or $USD/kL). These data will help set the foundation for examining unit costs, time savings, and behavior acceptance of proposed new systems.