Legionnaires' Bacteria Reemerges In Previously Disinfected Cooling Towers

schwit1 writes with the New York Times' unsettling report that 15 water-cooling towers in the Bronx that this week tested positive for Legionnaires' disease had been disinfected less than two months ago. From the NYT: After an outbreak of the disease killed 12 people in July and August in the South Bronx, the city required every building with cooling towers, a common source of the Legionella bacteria that cause the disease, to be cleaned within two weeks. ... [The] city found this week that bacteria had regrown in at least 15 towers that had been cleaned recently in the Morris Park section of the Bronx. The testing occurred after a fresh outbreak in that area that has killed one person and sickened at least 12, and spurred an order from health officials for the towers to be disinfected again.

Comments

Re:Uk legionella engineer here

[Pinky's Brain]

Yes, but LEDs don't go low enough on the spectrum. The lamps they use for ponds are gas discharge and don't last very long.

If you really want to generate UV it would make more sense to use spark discharges in the water. Generates a lot of UV, destroys bacteria due to electroporation, removes charge from particulates and decreases the size of particulates through shockwaves (also your electrodes of course, but those are cheap to replace).

The bacteria are found in the cooling towers

[mark_reh]

because it provides a good environment for them. It is not at all surprising that the bacteria would be found in a recently disinfected cooling tower. The only way to stop that from happening is to somehow make the cooling tower environment a less friendly one for the bugs.

Re:Yeah, I thought this problem was solved

[lgw]

A useful concept here is "Social Tech Level". We have the tech for safe nuclear plants, but we may lack the social tech. Much as, say, Panama had the tech to maintain the canal for many years before it had the social tech. You need both the technical know-how, and enough resources left over after corruption to actually fund it.

For all our competing systems of government, we don't seem to have made much progress in "social tech level" in the past 100 years. If anything, the basic systems of administration haven't improved in this regard, but the skill in corrupting them has gone way up (whether corporate corruption or good old fashioned Old Boys Network corruption).

Whether Socialist, Communist, or Capitalist, each in it's own way we can't seem to get the job done, so I think it's something quite distinct from economic system. I think there's just a problem of administration, transparency, and reporting results to solve. E.g., I don't care if the road gets built by the mayor's nephew, I care whether it's build on-time and to-spec, and how much it cost - if it merely cost more than it should, that's the least-bad problem. Cost-cutting is a good thing, but it takes a back seat to getting the actual job done.