ISLAMABAD -- Recovering from the devastating floods still battering Pakistan will take at least three years, the president said, as the waters swept south after leaving millions homeless and submerging millions of acres of farmland. The floods that began nearly a month ago with hammering monsoon rains in the northwest have affected more than 17 million people, the UN estimates. Most of the 1,500 deaths occurred early in the flooding, but the crisis still is growing. President Asif Ali Zardari defended the government's much-criticized response to the unprecedented floods but acknowledged recovery would take a very long time. "Three years is a minimum," Zardari said in an interview Monday with a small group of foreign reporters in the capital, Islamabad. The widespread misery caused by the floods has triggered worries about social unrest, food riots or even a challenge to the government's rule before its term ends in 2013. Local charities, the Pakistani army and international agencies are providing food, water, medicine and shelter to the displaced, but millions have received little or no help. Aid officials warn that widespread outbreaks of waterborne diseases such as cholera now pose a threat. On Tuesday, officials announced that the government would give 20,000 rupees ($230) to every family affected by the floods, with a statement from Zardari's spokesman calling the payment "initial assistance." In Shadad Kot, in the southern province of Sindh, authorities are increasingly worried that even the 11 miles (18 kilometres) of new levees soldiers have built may not hold back floods in the city, and in Qambar city further to the south. On Tuesday, workers piled stones and sandbags to plug leaks in the levees, trying to stay ahead of any damage to the defenses. Ninety percent of Shadad Kot's 350,000 residents have already fled the city. Since the floods swept the country more than three weeks ago, the Taliban and al-Qaeda have been relatively quiet. But on Monday, three bomb attacks rocked the northwest, one of which killed the head of an anti-Taliban militia on the outskirts of the main city of Peshawar. Zardari - whose wife Benazir Bhutto was assassinated by militants in 2007 - said the flood crisis would not distract from the campaign against militants. He reiterated earlier remarks that extremists could benefit by picking up recruits from hard-hit areas. "The fight goes on, on all fronts," Zardari said in the presidential palace with his foreign minister and key advisers sitting alongside him. "If you are fighting for a cause and the ... situation turns difficult, you don't give up. You bring new resolve to the table." The floodwaters, which have devastated lives from the mountainous north to the southern plains, are expected to begin draining into the Arabian Sea in the coming days.