• jadero
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    11 year ago

    It depends. If you’re on a system like I used to manage, gravity will get you water. We had no pumps for delivery. But the rest of the system required power, including pumps to get the water from the source into the water treatment plant. That means even the untreated water would eventually run out.

    • @[email protected]
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      21 year ago

      Do your cities not have backups? I’m in Canada and we have mandatory generator systems in all our water plants to ensure continued operation even with power outages - more meant for winter storms than summer blackouts, but same effect. They have a decently long minimum time they need to be able to operate for - a few days at the minimum. And summer brownouts typically (at least up here) are rolling, so they can just keep the water plant fully supplied while residential/commerical power is cut

      • jadero
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        21 year ago

        Heh, I’m in Canada, too. “Deep” rural Saskatchewan, where the nearest city is 200 km away. The water treatment plant I operated serves a community of 280 people. The treated water holding cisterns hold about 3 days of water and are on a hill above the village for gravity feed. There are no distribution pumps, so power outages have no effect on the ability to distribute water.

        The water source is a rural pipeline that serves several communities and many ranchers and farmers. You cannot connect to that pipeline without having your own 3-day storage capacity. That is to deal with pipeline faults, pump station faults and widespread power outages. There is no long term backup power at the pump stations.

        When the treatment plant experiences a power failure, the valve controlling incoming water shuts off to prevent the possibility of untreated water entering the cisterns. This is why there is no local power backup. There has never been a local power failure that took longer than 24 hours to restore. There has only ever been one widespread outage that took longer than 24 hours to repair and it was still short of that 3 day window.

        That is not to say longer outages are impossible, but it’s tough to get funding for something that is seen as “not gonna happen.”

        As far as I know, the cities do have some kind of backups, but given that a common recommendation is to keep a personal 3-day supply of water, I’m not sure what those backups are.

        • @[email protected]
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          21 year ago

          Ha, that’s funny. Nice to meet you! Just had a buddy get back from a backcountry hiking trip where he had to carry in his water - said the potash is so pervasive that you can’t filter out the water easily. I imagine for anyone in that area there’d be a number of other problems or considerations up there.

          Yeah, your treatment plant is far smaller than the ones I’ve been in or worked on. I’m a civil engineer and have helped design and commission a few water treatment plants, but I’m in a small city in the Golden Horseshoe, so we’re numbering tens of thousands treated for each treatment plant. They recommend three days water here too, but the treatment plants are designed to continue operating for a while after that.

          It’s an interesting view into the smaller system, especially the onus of 3-day supply being on ranchers/farmers. Most of those over here are on their own well water, and are SOL if they didn’t plan properly in power outages.

          • jadero
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            21 year ago

            Our rural pipeline system was put in to replace all the bad wells. The village used to run on well water, but even after treatment, water heaters typically lasted only 3-5 years and people typically bought their drinking water in jugs. Now the water comes from Lake Diefenbaker and requires only filtering and disinfection. When I was operating the plant, I worked with the Water Security Agency to put in an activated carbon injector to deal with occasional colour problems. We typically only had to run it a few months every few years. Nobody ever figured out what was introducing the colour, that I know of.

            Every few years someone at the WSA tries to shut down the pipeline because it doesn’t meet modern spec. In the absence of funding for a replacement, that would put everyone back onto those nasty wells that are usually untreatable by residential systems. I’ve participated in keeping that pipeline in service as the much lesser of two evils.

            Not all the wells are bad. There is one near my home (I don’t live in town) that is of such a quality that there are people in their 90s who’ve been drinking it raw their whole lives. I’m not that brave! I haul it to our cistern, then run it through a “base camp filter” (10 liter gravity filter with 3 ceramic filters rated for wild waters). The turbidity is so low that the filters last several years.

            You’re the first water treatment person I’ve ever met online!