The canyon's main aquifers were too deep to be of use to ancient Chacoans: only several smaller and shallower sources supported the small springs that sustained them.

However, since 2000 the depletion of China's main aquifers has led to an overall decrease in grain production, turning China into a net importer.

The Gaza Aquifer along the coast is the main aquifer in the Gaza Strip and it consists mostly of Pleistocene sandstones.

Furthermore, the actual volume available in the main aquifer would likely be less than estimated because of probable decreasing porosity with increasing depth.

Furthermore, the deep drainage system penetrates below the clay aquitard in some places into the main aquifer.

Complicating matters, no one knows the full extent of contamination of the main aquifer on Long Island.

There are two main underground aquifers that provide fresh water to modern day Israel.

The Southold Town Board recently balked even at reducing the density of residential construction over the town's main aquifer, although this step was urged upon it by Suffolk's top planners.

Natural precipitation remains our only cost effective drinking water source since Shelter Island's fragile main aquifer and its even more fragile peninsula sub-aquifers are completely independent of mainland Long Island.

The main aquifer is the Tecolutla, which has 70% of the underground fresh water in the area, followed by the Libres-Oriental, Martínez de la Torre-Nautla and Perote-Zayaleta.