Drinking Recycled Sewage

[mcflux]

Originally Posted by Smoked

Not Bad Dave, fairly accurate description of what is done. Most water is clorine treated, but UV and Ozone treatment is anoher disinfection technique.

Smoked & MO, cheers ;)

UV and Ozone means were more for sewage treatment weren't they? (which is still perfectly relevant to this thread I know)

Those UV lights pack a punch! One of my projects over summer was getting a powered hoist and railing installed to raise the baffles out of a UV chamber at a WWTP, so they could be cleaned by the plant operator without OH&S issues arising. The lights in the banks were hardcore, and interestingly enough green mosquitos were thriving within there! An eel swam up the outlet from the wetlands the treated sewage discharges into, and ended up in the chamber. I'm guessing it will die of cancer lol, but it was alive & kicking when we fished it out to release back into the wetlands.

As for chlorine treatment, my project last semester for uni was looking into Neerim South's water/wastewater infrastructure and consumption/discharge trends over the next 20 years. A note of interest was that Noojee's water supply is piped from Neerim South (approx 20km away, and 100m uphill), but it takes up to a fortnight for the water to travel between the towns.

Chlorination at Neerim South would not ensure that the water is still disinfected by the time it reaches Noojee, so Hypo (Hyperchloric or Hydrochloric acid/ammonia) is used instead for this supply, which doesn't pack the same punch as chlorine, but lasts far longer. Neerim South's supply uses chlorination still. The treated water comes from the one storage basin, but is split into two supply lines, hence the two different disinfection techniques applied here.

"Why not chlorinate at a point between the towns?" you may ask. Well, it would be a security issue to have some chlorine tanks sitting in the middle of nowhere, and it would mean more chlorine enters into the system, making the water taste like you're at the local swimming pool.