Abstract

Groundwater reserves are recharged for the most part by rain that infiltrates through the soil into the underlying layers. These reserves are occasionally augmented by streams and rivers that loose water to the underground strata. Once underground, the water flows at rates ranging from more than 10 meters a day, to as little as 1 meter a year, until it reaches an outlet. This may take the form of a spring, or of a system of slow seepage at the ground surface. It is this seepage that kept rivers flowing during dry periods.

Some 2500 years ago, the use of "Qantas" was developed in Iran. These are long, horizontal galleries, connecting aquifers at the foot of mountains to fields and villages several kilometers away. The use of Qantas spread, as far afield as Egypt, China and Afghanistan, and many such streams are still used today. Once pollutants reach the water, it, may take a very long time to flush out the aquifer completely. Furthermore, pollution can take a very long time to show itself since the water within aquifers moves so slowly.

Northern coastal regions of the Persian Gulf include major riverine systems. These are Karkheh, Karun, Maroon - Jarahi, Zohreh, Shapor-Daleki, Mand, Sahel Jonoobi, Kal, and Minab-Bandar Abbas. The total area covered by these water resources systems is 363381 km².

Annual precipitation is about 185 mm in Kerman Province to about 250 mm in Khuzestan and greater in provinces located in the Zagros mountain ranges. Most of the rain and snow precipates in winter and early spring. Shallower underground water resources are sued for agricultural irrigation and drinking. The pollutant affects of the 1991 war of Iraq against Kuwait, on water resources, have been obvious since the measured data of acid rain and black rain (soot), showed the contamination of water resources used widely for drinking, irrigation, and industrial purposes. Once polluted, aquifers are difficult, in fact, sometimes impossible to clean up. Samples of water (both surface and underground) from Khozestan region have had contaminating compounds following the burning of Kuwait oil wells and precipitation of black rain. Since contaminated rain incidences accounted for about 30% of the annual regional of underground water depositions (a total of 13353 ´ 10⁶ m³); i. e. 4 ´ 10⁹ m³ of contaminated waters.