metering of handpumps using domestic meters
I know this almost a repeat question but I don’t think we really arrived at the answer. http://knowledgepoint.org/en/question...
I am interested in metering hand pumps for monitoring and evaluation (not for payments). I am aware of the exciting new developments in remote meters (smart hand pumps (oxford), sweet lab, welldone and charity:water).
I was wondering if anyone has had success with cheap, commercially available meters linked up with some sort of mobile/cell phone system (mWater, see/saw, AKVO).
The example of a domestic metered hand pump indicated that meters failed after one month http://www.uwasnet.org/Elgg/file/down...
The meter should be able to: deal with turbid water, operate without mains electricity, and handle low flow rates and profiles (half filled pipes, air pockets) associated with hand pumps in our areas.
It seems like the only meters built to deal with turbid water are agricultural which cannot pick up low flow rates.
Finally, the meters need to be cheap.
Thanks so much for your time!
All the best, Orlando
Thanks for sharing such an impressive amount of background research on this issue. We (mWater) have done projects in the past where we used bluetooth to connect a sensor to our app, so that is definitely an option to consider. I also would suggest seriously considering a manual meter that is reported by someone with a smartphone.
Last year, our partner Sparx Engineering built a GPS sensor that tracked the number and distance of trips women made gathering water. Battery life was the key challenge, so we did not go with a cell phone data connection but rather stored the data for two weeks and then downloaded it via bluetooth to the mWater app, which then synchronized it with our server once a connection was available. This works very well when you want to conserve battery life and real time data is not the objective (i.e. M&E applications).
After hearing more about your objectives, the groundwater hydrologist in me thought that you should also consider measuring the depth to water, in order to understand what might be contributing to lower yields in certain dams (such as rapid infiltration versus over-abstraction of water). This can be done using electronic level loggers, but a simple dip meter used by a field worker also works just fine if you don't need high time resolution.
So, given your objectives, I think the manual flow meter approach is worth considering but as you mentioned, most of these meters are designed for municipal piped water, which is very low in dissolved solids and particles. You would need to install a screen ahead of the meter to prevent damage caused by particles of sand or iron from the pump, and clean this out often. I would at least do a pilot test with just a few devices before scaling up the approach.
As far as electronic options, I think WellDone is a good path since they are building a modular system that will soon include an ultrasonic or hall effect sensor for non-intrusive monitoring. You should ask Austin for more information about the data issues, but we have talked several times about building a WellDone integration with the mWater app for data transfer and I would be very interested in moving forward if there was a business case for this.
I also would not put much faith in the charity: water sensor, which is very far behind the announced schedule and still doesn't seem to be available to anyone outside their organization. Also, that sensor is designed to only work on Afridev pumps and requires removal of the pump head for installation. Since your purpose is to perform a representative study, you presumably would want to rotate equipment to different project sites at different times.
Let me know if you have any questions and feel free to get in contract directly john @ mwater.co.
Thanks for the great feedback! lots of questions to answer so themes are in bold.
It seems like the advice is either to do an observational study, use a remote meter, or don’t do it at all. We have some specific barriers that may make using remote meters in some locations challenging (listed below) but not impossible.
We hopefully will use remote meters in the future but I am interested in understanding all available options for comparison before moving ahead.
Just to reiterate the need for a robust meter: It seems like one could get useful abstraction data using a domestic meter, that works with sub-optimal water conditions, monitored by a community member with a cell/mobile phone, who reports readings through an established system (see/saw, mwater, akvo).
As such, I am not looking for a pre-existing version of charity:water etc’s device, but alternatives currently on the market that could produce similar data.
I’m new to this and charity:water’s device is the one I have researched the least. Why charity water might not be best for my needs
• Bad GSM coverage. I work on sand dams, which by design are located in valleys, and most of our projects are in areas with poor coverage, so technology reliant on GSM coverage on site wouldn’t work across all our locations. It might get complicated if we have several different monitoring systems. In areas with patchy GSM coverage reporting could still be done by an individual, they could take the reading from the domestic meter, find a spot with better coverage, and send the report even with an old nokia. (its not ideal, but it would extend the areas where remote reporting was suitable)
I am aware some of these devices (like austins welldone(not yet on the market)) are blue tooth enabled.
• If there is a low tech solution that works and is proven it seems like it would be worth exploring for comparison.
Good point about turbidity. Turbidity is a problem with metering across many African water utilities (8 min into this video https://www.youtube.com/watch?v=Sgi9t...) I don’t have great turbidity data for all our partners, but those who do monitor usually <5 NTU but occasionally higher. I have personally tested with greater NTUs than this (especially if they have been out of use for a short time)
Some meters block/jam and give false readings when turbidity is high even for a short time (likely the cause of blockage in the above articles). The remoteness of our projects means that blockage is not acceptable.
Having spoken to meter manufacturers, even low NTU values can result in damage. (my understanding is Welldone have addressed this problem, it isn’t a problem for “smart pumps” due to the accelerometer, and sweetlab weren’t too clear, though that was a long time ago.)
Cheers for the observational study advice (phone, buckets, stop watch). This will be the solution if all ... (more)
How do your requirements differ from charity: waters? https://www.charitywater.org/blog/wan... They wouldn't have passed google.org's due diligence if the same could be done with a cheap commercially available meter hooked to a cheap commercially available GSM module.
How turbid is your water? there has to be a point above which treatment at source becomes a necessity, unless of course you are just irrigating with the water..?
At low scale, the best solution could be a trained local user, with an affordable phone (including a stopwatch facility) and a measuring cylinder/bucket, who gets paid per experiment to run whatever flow tests you need & report back by SMS.
It is difficult to see what value could be gained from monitoring the flow from hand pumps, easier to estimate the number of containers used by the community if you are checking for wear and tear on the pump or needing some monitoring of the aquifer...there should always be some means of raising funds to pay for pump maintenance or the pump will soon be out of action...
This thread is public, all members of KnowledgePoint can read this page.