How to judge the drinkability of water whatever its nature

[abouabdelmajid]

I would like to design a system that allows to judge the potability of water after having made a certain number of measurements with the available sensors such as the PH sensor, turbidity, temperature, TDS meter...

after some research I found that there are 8 essetial parameters that once respected their values we can say that the water is 100% drinkable. The settings are:

- pH (PH sensor)
- Turbidity (turbidity sensor)
- Color
- Conductivity
- Total dissolved solids (TDS metre)
- Hardness
- Temperature (temperature sensor)
- chlorine (Redox sensor

So I told myself that we have to get sensors for each parameter and with arduino we will be able to know the good results.

Am I thinking right? I exaggerated at the level of many parameters? do I have to add others or eliminate some of them?

 

[chemelec]

Bacteria would be my biggest concern.
Maybe add a Microscope?

 

[abouabdelmajid]

i ve never tought about that Mr chemelec. Can a microscope replace all those sensors i talked about ? If that so should i use an electronic device that can do the same thing and attach it to arduino ? can u give me more details about that sir ?

 

[Pommie]

I think the smiley face was supposed to be a clue.

Mike.

 

[dknguyen]

i ve never tought about that Mr chemelec. Can a microscope replace all those sensors i talked about ? If that so should i use an electronic device that can do the same thing and attach it to arduino ? can u give me more details about that sir ?

You need to narrow your requirements so you can ignore certain things since it's impossible to test for everything. For example, where is this water coming from? For example, heavy water.

 

[ronsimpson]

Easy test: get someone to drink the water and see if they get sick.

 

[ChrisP58]

I would suggest identifying all the possible things that could be in (or about) the water that could make it non-drinkable.

Then list all of the measurements you need to detect/quantify those items in your sample.

 

[gophert]

Easy test: get someone to drink the water and see if they get sick.

Finally! You found a use for all those thousands of "friends" one can connect with on Facebook.
Me, "Hi, Friend, have a drink of this river water"
Friend, "Is it safe?"
Me, "Of course, would a friend try to make you sick? But please let me know if you suddenly catch that stomach flu that is going around."

 

[ronsimpson]

Hi, Friend, have a drink of this river water

I like hi-tech but some times there is a simple way.
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Years ago I was hunting in the high mountains with some friends from far away. We were 1 mile from snow. The river was very clean. The friends dumped out their "city" water and fill their jars with mountain water. They drank large amounts of mountain water. We walked about 100 feet and there in the river was a dead deer.

 

[Reloadron]

So I get to thinking how do I know for sure my city tap water is safe to drink? Then too I am of the conviction that adding a few drops of chlorine bleach to a quart of water makes it safe to drink and if it taste bad a packet of plane unsweetened grape Kool Aid can fix it.

Ron

 

[ronsimpson]

city tap water is safe to drink?

Where I live most cities are on rivers. Each city pulls water out of the river, cleans it, drinks it, flushes it down, cleans the water again and puts it back in the river. Then the next city pulls water out ..........

How many times has your water been used?
-----edited------
This topic is serious. Millions of lives hang on the question/answer. And I am joking.

 

[gophert]

Where I live most cities are on rivers. Each city pulls water out of the river, cleans it, drinks it, flushes it down, cleans the water again and puts it back in the river. Then the next city pulls water out ..........

NASA is thankful that those river cities proved it is possible before they implemented it on the International Space Station.

 

[Reloadron]

How many times has your water been used?

Now that you mention it I really don't know. Here in Cleveland we draw our water from Lake Erie using a crib about 5 miles out. While off topic I can share this. The Western Basin of the lake which is shallow has been suffering from algae blooms and a few places well west of us have had some serious issues with their drinking water as a result. Their cribs are not as far out as Cleveland's are. Shallow portions of the lake run warmer and the algae thrives.

Under normal conditions water is pumped from the lake. That water goes back into the lake after a water treatment plant. The big problem comes with heavy rainfall. Storm sewer runoff goes into the lake but much of it finds its way into the sanitary sewer system. The treatment facility literally overflows resulting in untreated sanitary sewer water going into the lake. Local beaches on the lake are closed for swimming as the bacteria thrive.

Where I live I am at the top of my street, the high ground. All of my downspouts run to the storm sewer line and sanitary sewer to the sanitary sewer line. Unfortunately for those at the bottom of the street large numbers of residences run both sanitary and storm into the sanitary sewer. Severe rain and basements down the road can fill with human waste. You can never have too much Chlorox on hand.

Ron

 

[shortbus=]

Where I live I am at the top of my street, the high ground. All of my downspouts run to the storm sewer line and sanitary sewer to the sanitary sewer line. Unfortunately for those at the bottom of the street large numbers of residences run both sanitary and storm into the sanitary sewer. Severe rain and basements down the road can fill with human waste. You can never have too much Chlorox on hand.

It was like that around here too. But a few years ago they(sewer dept) started doing "smoke tests" on the sewers. If smoke came out of peoples down spouts they were given an amount of time to get the downspouts out of the sanitary sewer lines. If they didn't they were fined and the sewer dept. did it and put the cost on their taxes or water bills.

 

[dknguyen]

It was like that around here too. But a few years ago they(sewer dept) started doing "smoke tests" on the sewers. If smoke came out of peoples down spouts they were given an amount of time to get the downspouts out of the sanitary sewer lines. If they didn't they were fined and the sewer dept. did it and put the cost on their taxes or water bills.

I didn't even know there were separate lines. Why does the sanitary line have an opening to the outside where someone can route their downspout to it anyways? (I'm imagning something that looks like a storm sewer drain but is for the sanitary line).

Actually, I'm not sure why you run a downspout to a storm sewer line to begin with. Don't people just run it onto their lawns?

 

[gophert]

Don't people just run it onto their lawns?

No.

 

[gophert]

Why does the sanitary line have an opening to the outside where someone can route their downspout to it anyways?

The sewer is not "open". The downspouts run into PVC pipe that connects to the pvc drainpipe.

 

[dknguyen]

The sewer is not "open". The downspouts run into PVC pipe that connects to the pvc drainpipe.

I've never seen that before. Here, everyone's downspouts just go onto their lawn. No dedicated pipes to drain downspouts.

 

[Nigel Goodwin]

In the UK water comes mostly from reservoirs (via the rivers), or via pumps from natural underground reservoirs. The water is processed before been delivered to the customers.

Waste water (from roofs etc.) is sent down different systems to sewage, the sewage is treated in sewage works, and the resulting clean water is returned to the river network.

As others have mentioned, water from the roofs is collected via gutters (modern plastic, or old cast iron) and sent down the 'clean' sewer system.

I've always been staggered on American TV programmes where you see houses with no gutters, and water just pouring off the roofs

 

[Reloadron]

I've always been staggered on American TV programmes where you see houses with no gutters, and water just pouring off the roofs

That sort of depends on where you are at. Just for example I live in Bedford Heights, Ohio, USA. Rural areas have fewer or no local codes to follow while the cities and towns have assorted building codes. I would assume GB is about the same. So in my little world of Bedford Heights, Ohio over the years the city codes have changed but like many city codes the changes applied only to new construction. All residences and commercial buildings now must have gutters and down spouts. All of the rain water runoff must go into the storm sewer lines.

It was like that around here too. But a few years ago they(sewer dept) started doing "smoke tests" on the sewers. If smoke came out of peoples down spouts they were given an amount of time to get the downspouts out of the sanitary sewer lines. If they didn't they were fined and the sewer dept. did it and put the cost on their taxes or water bills.

Bingo and when they start doing that around here people start getting real nervous.

Here's an interesting note. Years ago where I retired from we used Therminol® 66 Heat Transfer Fluid which is not exactly a common item. We used it with some heat transfer systems. It was expensive and it needed proper disposal. Actual we sent it back to the manufacturer who charged us, filtered and cleaned it, and sold it again. Anyway one day we get a call from the Cleveland Regional Sewer Division. They actually detected trace amounts of the stuff in the sewer system and we were the only guys using the stuff for a hundred mile radius. Go figure. We had a pinhole leak in a heat exchanger. Amazing they were able to identify the stuff, contact Monsanto Chemical who makes it and narrow it down to us.

I guess another big problem is people disposing of prescription medications down toilets.

Ron