What methods might an ancient civilization take to extract fresh water from great depth?

I previously asked What measures might an ancient civilization take to protect itself from extreme heat? The answers gave some useful suggestions as to how cities could be adapted. For convenience in the next question I will call these people the "Androy".

The principle Androy city is now suitably adapted to the heat, but uses a lot of water. The aquifer they rely on is becoming depleted and on average each year the Androy need to delve an additional meter to ensure that their supply of water is maintained.

Assuming the aquifer is as deep as necessary, what methods could the Androy use to maximise the water extraction process, roughly how deep can they get and what ultimately prevents the Androy from obtaining enough water?

Assume a surface layer of sand and mud with a water bearing sublayer of limestone 5 - 10 meters below.

The city population is at least 50,000 but may be adjusted if it helps

The Androy can use any technology that was available to any ancient society in our world prior to 400 CE

Note this is the second in a series of four related questions

Edit A hand dug well 1285 feet deep seems possible! http://www.mybrightonandhove.org.uk/page_id__6948.aspx Point od interest from my researching

posted about 7 years ago

Slarty‭

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