An example of the value of natural surveillance (a/k/a "eyes" on the street or in this case "noses")

Natural surveillance is what Jane Jacobs called "eyes on the street."

KIRO-FM reports, "Alert dog walker likely prevented Bremerton explosion," that in Bremerton, Washington, a person out walking their dog noticed a pronounced smell of natural gas and called the local gas utility. They started checking the neighborhood and found a house with high readings. They called emergency workers who entered the house. Readings exceeded the level where explosions are likely to occur. The resident said she accidentally left her stove's burners on when she had been cleaning.

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While looking up this story, I found another interesting one... since marijuana has been legalized in Washington State, police dogs trained to find drugs have to be trained on smells other than MJ. See "Some Wash. police dogs not smelling pot anymore" from KIRO-TV.