The Appian Way (Via Appia Antica) is an ancient Roman military road that was built to connect Rome, Italy, to Brindisi 350 miles to the southeast. Built between 312 to 264 BC [1], with sections still in existence today, it represents one of the rare infrastructure artifacts that has lasted more than two millennia. The Appian Way serves as an example to frame the question – Is there a lesson to be learned that will move forward the design of resilient ultra-longevity urban roads? The answer is yes. However, not because of new materials or technology, but by considering how the paradigm [2] has changed. The Appian Way was not built over other aging and decaying infrastructure unlike our modern urban roads. As Donella Meadows stated: “Paradigms are the sources of systems” [3] and “…the places to intervene in a system begin with understanding the goals of the system and the paradigm out of which the goals, rules, feedback structure arise”. [4] In other words, the goals of new urban smart roads (e.g. improved data collection, traffic efficiency, and safety) are limited by the paradigm that the road exists within. The current heavily trafficked urban road paradigm consists of a pavement underlain by assets [5] from multiple sectors [6] of infrastructure [7], each in different states of decay, each sector governed by a utility [8], and placed in the underlying soil matrix. The term ‘decay’ is preferred when describing the vulnerabilities of urban infrastructure as it encompasses aging, but also includes the threats of corrosion – at any age – from being buried in a soil matrix (discussed further in Part 2). For purposes of this blog, I will refer to this as the Road and Buried Infrastructure Decay (RABID) paradigm.
The RABID paradigm is found in any city in the United States, and the indicators of its presence has become an accepted part of daily urban life, as shown in Figure 1. But, consider these juxtaposed pictures in Figure 1 from an ownership perspective. The photo on the right represents the utility ownership point of view by marking their respective assets with a particular color spray paint. While the photo on the left represents the city resident and business experience – the road is closed. The concern for the residents and businesses in a city is not what sector of infrastructure is being repaired that day, but the resulting disruption.
Of course, the RABID paradigm is now generations old and the problems have always been evident. Frühling described the increasing complexity of different infrastructure utilities causing disruption to urban life in London and asking for more city government oversight in 1910 [9].
"There are special conditions in the English capital because not only is traffic increasing constantly but also the supply networks are in the hands of different bodies who have received - each for themselves alone - the rights from Parliament also for tearing up the road for their purposes without official permission."
Frühling was commenting on the disruption caused by the RABID paradigm (in concept) from a city’s perspective, not from a single sector utility perspective. He noticed the potential impact that any failed infrastructure would have on the residents and business owners in a city [10]. Nearly 110 years after Frühling’s observation, it is apparent that the RABID paradigm is not agile enough to allow access to maintain the buried infrastructure without disturbing city life. And, as the buried infrastructure continues to decay, city leadership (e.g. city manager, mayor, and senior staff) must recognize how disruptions caused by failing infrastructure thwarts any claims of being a truly ‘smart’ or a ‘resilient’ city. And, city leadership should consider the value of achieving a truly smart/resilient city status for inclusion in cost considerations (discussed in Part 4 of 5). Consider a few of the inefficient characteristics of the RABID paradigm:
75% of water utilities in the United States cite pipe breaks as a key criterion in pipe replacement decisions [11] due to inaccessibility and the time to permit road closures for maintenance.
The average age of a failed water main is only 47-years [12]. Therefore, the utility is only extracting about half of the life expectancy of an asset [13]. The key causes of failure can be attributed to the RABID paradigm: soil corrosion, poor (hurried) construction, and deferred maintenance (inaccessibility). In fact, corrosion and construction related failures are so prevalent that age-related failures only account for about 20% of all potable water main failures [14, 15]
Even though the locations of buried infrastructure are to be marked by each utility prior to repair and maintenance (as shown in Figure 1, photo on right), mistakes are common and damage to buried infrastructure costs New York City, as one example, an estimated $300 million every year [16].
In order to achieve smart city goals, the ‘rules’ of the urban road paradigm must be changed to create an environment for smart goals to be realized. As there are no smart technologies that reverse infrastructure aging, the new paradigm is not a technological solution, but a new physical configuration that eliminates the threats created by RABID, at least in critical urban corridors (discussed in Part 5). However, a new utility paradigm will not be championed by a single utility alone. A broader perspective, a city’s perspective, is required to present the overall social and cost benefits to the city and all utilities. City leadership must be able to engage with the utilities as an equal stakeholder. This process of city leadership empowerment begins with identifying existing data and trends to form a customized set of key performance indicators (KPIs) to better characterize urban disruption and the economic and social consequences when assets fail. These will be discussed in the following parts.
The next parts to this every other Tuesday blog include:
Footnotes
[1] Retrieved from: https://en.wikipedia.org/wiki/Appian_Way
[2] Definition: noun. an example serving as a model, or a framework containing the basic assumptions
[3] Meadows, Thinking in Systems, a Primer, 2008 ISBN-13: 978-1603580557
[4] D. Meadows, 1997, retrieved from: http://www.wholeearth.com/issue/2091/article/27/places.to.intervene.in.a.system
[5] ‘asset’ is defined as a component of an infrastructure sector (e.g. energy) or subsector (e.g. gas main)
[6] ‘sector’ refers to the individual infrastructure systems that delivers an essential service to the city, for example, transportation, energy, water, sewer, solid waste, stormwater, etc. through pipes, cables, vehicles, pavement, etc.
[7] ‘infrastructure’ in this paper refers to buried sectors, not overhead and does not include buildings.
[8] ‘utility’ is the entity that operates and maintains one or more of these infrastructure sectors. And each utility may be a department in municipal government, or a concessionaire granted a monopoly over a geographic area, a private infrastructure provider, or a public-private partnership (PPP).
[9] Frühling, Retrieved from: http://www.unitracc.com/know-how/fachbuecher/rehabilitation-and-maintenance-of-drains-and-sewers/rehabilitation/replacement-en/utility-tunnel-en
[10] ‘city’ is the collective urban area that relies on these essential infrastructure systems to maintain economic, social and governance services
[11] WRF. FAQ's. Retrieved from http://www.waterrf.org/knowledge/asset-management/breaks-leaks/Pages/faqs.aspx Retrieved in January 2019
[12] Folkman, S. (2018). Water Main Break Rates in the USA and Canada: A Comprehensive Study. Mechanical and Aerospace Engineering Faculty Publications, Paper 174. Retrieved from https://digitalcommons.usu.edu/mae_facpub/174
[13] AWWA. (2010). Buried No Longer: Confronting America’s Water Infrastructure Challenge. Denver, Colorado: AWWA.
[14] Berger, D. (2011). Understanding asset failure. Retrieved from https://www.plantservices.com/articles/2011/09-Asset-Manager-understanding-asset-failure
[15] Davis, P., & Marlow, D. (2008). Asset management: Quantifying economic lifetime of large-diameter pipelines. Journal - American Water Works Association, 100(7), 110-119. doi: 10.1002/j.1551-8833.2008.tb09680.x
[16] Bloomberg News, retrieved from: https://www.bloomberg.com/news/features/2017-08-10/nobody-knows-what-lies-beneath-new-york-city?src=longreads