Agriculture in Syria runoff most of the year. The river flows southeastward across the arid Syrian Plateau into Iraq, where it joins the Tigris River shortly before emptying into the Persian Gulf. In addition to Syria, both Turkey and Iraq use dams on the Euphrates for hydroelectric power, water control, storage, and irrigation. In the mid-1980s, about a half of the annual Euphrates River flow was used by these three countries. Syrians have long used the Euphrates for irrigation, but, because the major systems were destroyed centuries ago, they now make only limited use of the river's flow. In the mid-1980s, the Euphrates
Ponnaiyar River river. The river is dry for the most part of the year. Water flows during the monsoon season when it is fed by the south-west monsoon in catchment area and the northeast monsoon in Tamil Nadu. However this water flow raises the water table throughout the river basin and feeds numerous reservoirs/tanks. The old river Dakshina Pinakini does not exist anymore. Substantial part of Bangalore's sewage enters this river via Bellandur and Varthur Lakes and other channels. The sand build of the river is quite impressive, suggesting that it may have been a perennial river with much larger water flow