As a hydrogeologist trained at UWI Mona. They say this because the Mona dam was built to service 750,000 people. Kingston now has over 1.5 million people double its capacity. Also I’m certain the bottom of the reservoir has so much sediment it’s capacity is at least 10% less. https://twitter.com/jaysononstage/status/1303757768189448192

Which makes the situation even worse. So “water levels are low” is a combination of excess water returned to rivers and KIN having more people than the dams have capacity for. Also it takes time for rainfall to leave the mountains and arrive at the dam, yes it takes over a month

To answer some of the DMs I got. Kingston and surrounding areas have groundwater but it is NOT safe to drink. And the cost of treating that water to WHO standards is enormous and more than building new reservoirs and water infrastructure to bring water from the Rio Grande.

To top it off. Pumping groundwater from under Kingston and surrounding areas may result in the entire city sinking from the mere fact Kingston is built on a mixture of limestone and alluvium. Alluvium is unconsolidated sediments.

Which pretty much means that at this point. Water in the pores of the underlying geology is what gives support to all the buildings and structures on top of it. Remove that water and the sediments will start to consolidate which means things ago start sink.

For example. The capital of Barbados Bridgetown. The parliament buildings are sinking ever so slightly to the point many decades ago the clock tower was moved to the other side of the parliament building to slow the sinking. A few cms over a few decades adds up over time.

To add to everything above. Certain times of the year withdraws are less from the reservoir than the influx into the reservoir (surplus) or equal (net Balance). Hence why certain times of the year there is water and other times of the year there isn’t.

There isn’t any because the influx is less than the withdrawal (deficit). So at some point. Something has to give and that’s withdrawal.

Also keep in mind. The water in Kingston isn’t just for homes. There are other industries connected to the water supply of the Kingston metro that use magnitudes more water than households. All these things draw from the same sources of potable water.