You dont actually need an (expensive) full range pore pressure transducer. You only need to detect pore pressure in the +1kPa to (say) -10kPa range. I suggest you look to soil science technology and the old 'gypsum block' technology which measures the AC resistance between two electrodes in a block of gypsum . for a full description see http://agriculture.vic.gov.au/agriculture/farm-management/soil-and-water/soils/gypsum-blocks-for-measuring-the-dryness-of-soil www.mea.com.au sell a good low cost logger and (manual) reader for these sensors. But any logger which measures AC resistance will work OK. loggers which measure DC resistance are doubtful as they cause polarisation (bubbles) on the electrodes .

NOTE that neither of the sensors on the market will read accurately at near zero pressure - I suggest you build your own sensor with two electrodes in a porous chamber filled with fine sand, and a pellet of gypsum to ensure some conductivity. (similar to the Watermark sensor) - 200u sand with a small amount of silt will give you a response curve from 0 to 5 kPa.

Just an idea - is it possible to take it as a parameter and for a standard case simulate to get expected results?

You dont actually need an (expensive) full range pore pressure transducer. You only need to detect pore pressure in the +1kPa to (say) -10kPa range. I suggest you look to soil science technology and the old 'gypsum block' technology which measures the AC resistance between two electrodes in a block of gypsum . for a full description see http://agriculture.vic.gov.au/agriculture/farm-management/soil-and-water/soils/gypsum-blocks-for-measuring-the-dryness-of-soil www.mea.com.au sell a good low cost logger and (manual) reader for these sensors. But any logger which measures AC resistance will work OK. loggers which measure DC resistance are doubtful as they cause polarisation (bubbles) on the electrodes .

NOTE that neither of the sensors on the market will read accurately at near zero pressure - I suggest you build your own sensor with two electrodes in a porous chamber filled with fine sand, and a pellet of gypsum to ensure some conductivity. (similar to the Watermark sensor) - 200u sand with a small amount of silt will give you a response curve from 0 to 5 kPa.

I think that cliff give a very good answer. The sensor from the market not necessarily achieve the accuracy that you need, so the best is to get your own sensor.

Good Luck!!

From my experience, I measured vary water level in slope by 6 observation wells, when there were rainfall in area. But in your case, you need sentitive data. I think I recomend Mr.Cliff's answer.