Heavy Rains and Dry Lands Don’t Mix:
Reflections on the 2010 Pakistan Flood

By Michon Scott. Design by Robert Simmon April 6, 2011

Each summer, monsoon rains sweep across southwestern Asia, soaking India and Bangladesh. In nearby Pakistan, the rains are usually less intense, more intermittent, and centered in the northeast.

Photograph of a family escaping the floods in northwestern Pakistan by boat.

Flooding forced millions of Pakistanis to flee their homes in July and August 2010. (Photograph ©2010 Abdul Majeed Goraya/IRIN.)

The summer of 2010 was different. In July and August, rain fell over most of Pakistan and persisted in some places for weeks. The Pakistan Meteorological Department reported nationwide rain totals 70 percent above normal in July and 102 percent above normal in August.

Rivers rose rapidly, and the Indus and its tributaries in the northern part of the country soon pushed over their banks. As the surge of water moved south, it swelled the Indus in Pakistan’s central and southern provinces. Then the problems started compounding. In Sindh, a dam failure sent the river streaming down an alternative channel west of the valley. The resulting floodwater lake—which merged with existing Manchhar Lake—spread over hundreds of square kilometers.

Map of the total extent of flooding in Pakistan during 2010.

Floods covered at least 37,280 square kilometers (14,390 square miles) of Pakistan at some time between July 28 and September 16, 2010. Relief agencies used maps derived from satellite data to direct aid to many of the victims and to plan recovery efforts. (Map by Jesse Allen and Robert Simmon, using data from UNOSAT.)

Even after the monsoon rains subsided, waters retreated much more slowly than they had advanced. Months after the rains stopped, crops, homes, businesses, and entire towns were still submerged. In some places, there were few means of water dispersal beyond waiting for it to evaporate.

The U.S. Agency for International Development estimates that the Pakistan floods affected more than 18 million people, caused 1,985 deaths, and damaged or destroyed 1.7 million houses. It was perhaps the worst flood in Pakistan’s modern history.