Infrastructure Vulnerability and High-Performance Integrated
Control (H-PIC). Europeans live in cities of compressed
spatial extent, with an imploded set of water uses and much
curtailed "recycle loops" between the output residuals
of one community and the inputs to the next. Under these conditions
it should be obvious that operation of the conventionally separate
parts of the urban wastewater infrastructure (the sewer network,
the wastewater treatment plant, and the receiving water body)
should be properly coordinated in a seamless, integrated manner.
Reliability of performance will also be at a premium, since
faults and failures will propagate swiftly and widely in a highly
inter-connected system of water uses. For over a quarter of
a century we have been working towards what we now call H-PIC:
the notion of adjusting, in real-time, the operation of the
wastewater infrastructure as a function of the current state
of the receiving water body. Recent results, from a project
with the Department of Civil and Engineering at Imperial College
in London, have demonstrated the technical potential of integrated
control of the entire infrastructure (Integrated Urban Water
Managament, or IUWM). We have also been exploring the problem
of screening design and operational options under uncertainty.
Our program seeks to encourage transfer of this European school
of thought to North America, where rapidly urbanizing metropolitan
regions, such as the city of Atlanta, require progressively
more intensive exploitation and re-use of the now very clearly
limited resources of the Chattahoochee watershed. What can Ecology
do for the engineering system of urban water infrastructure?
The ecologist's caricature of the control engineer has him/her
slavishly pursuing the brittle and vulnerable invariance of
pinning the system's behavior down to an automated constant
equilibrium, that is, the pursuit of engineering resilience.
If we have now models by which to cultivate IUWM, they should
be turned as well to developing ecological resilience in the
performance of the web of technologies spun together into the
metropolitan water infrastructure. And that would be H-PIC.