simplicity, such sensor systems might focus on baseline properties like turbidity or ultraviolet absorbency, which may be indicators for the addition of a contaminant.

Conventional wisdom holds that water’s dilution effects would necessitate large quantities of contaminants to pose health problems, but this conjecture is poorly supported by research. The point needs more careful analysis to determine precisely what agents, and in what quantities, pose a serious threat if present in a potable water supply. Further, sensors should be deployed that will be effective in continuously testing the water supply to determine with confidence whether it is safe. If installed in distribution systems, these sensors would likely be effective at determining the presence of backflow-introduced contaminants.

Recommendation 8.14: Research and development are needed to create sensors and supporting systems for monitoring the safety of drinking water. These sensor systems would continuously test the water supply for agents in sufficient concentrations to pose serious threats; they would signal a response site, or automatically close valves, as needed.

Decision Models and Sampling

Important research questions include what to monitor and sample in the water system, as well as when and how; what inferences to draw from the data; and what the resulting optimal decisions should be.

Recommendation 8.15: Research should be undertaken on water sampling schemes to determine what types and population of data points are required for a spatiotemporal network and on intelligent decision processing to be able to reliably recognize the pattern of attack indicators vs. natural hazards. Such research would require that priority attention be given to the development of simulation models that would both analyze and simulate events and serve to train operators in systematic recovery, emergency response, and evacuation.

Interactions Across Infrastructures

The water infrastructure depends on electricity to control pumps, valves, and other mechanical components, as well as to power sensor, computer, and telecommunications systems. Disruption to the supply of electricity would thus have a major effect on water supply and treatment. Similarly, an important design requirement of most urban water systems is adequate water pressure for fire protection; an attack that ignited urban fires and disrupted the high-pressure hydrant system at the same time could therefore cause great damage and loss of life. Research is needed to understand the extent of these interdependencies and to create strategies for effectively dealing with them. This is a crosscutting issue that is covered in Chapters 10 and 11.

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement