( CNN ) -- The statistics are devastating , but for aid workers like Faisal Kapadia and Awab Alvi , witnessing the despair from the Pakistan flooding was far more tragic than they imagined . `` You can see 8,000 to 10,000 people in Sukkur in the road , sleeping in the mud , '' said Kapadia , a resident of Karachi . `` All the people are sitting on the side of road , defecating there , drinking water there , living there . '' Roughly 4 million people are homeless from mammoth flooding that covered much of Pakistan for three weeks . Hundreds of health facilities are damaged or destroyed . Millions are at risk for deadly waterborne diseases from the filthy flood waters . Officials estimate the death toll between 1,500 and 1,600 , but Kapadia says he thinks the numbers could skyrocket as water recedes and more bodies and animals surface . `` Everywhere we go we see eight to 10 feet of water , '' said Kapadia , who traveled through inundated villages between Shikarpur and Sukkur . `` All we see are the tops of houses . '' Just a month ago , Kapadia was a recreational rider in the 4x4 Offroaders Club of Karachi . He did n't expect to use his off-roading skills to deliver life-saving supplies to flood victims across nearly impassible terrain and waters . `` We never thought of that , '' Kapadia said . `` But when you see things happen like this , you ca n't just sit on the side and watch thousands of people die . '' So club members , family and friends raised money for supplies to the neediest survivors . So far the 4x4 Offroaders Club of Karachi has distributed 100 tents and about eight truckloads of food . In Sukkur , where refugees are arriving en masse , the riders have distributed at least 400 hampers of food . Each hamper contains 5 kilograms of flour , 5 kilograms of rice , a liter of oil , salt , tea and water . But the work has n't been easy . The stench of filth permeates the air . Skin blisters surface from temperatures reaching 48 degrees Celsius ( 118 degrees Fahrenheit ) . Kapadia said he ca n't shake the image in his mind of young children chasing him as he tossed water from a moving truck . The truck was moving at least 30 kilometers per hour , but he could n't slow down . Mobs of hundreds have pounced on aid workers delivering food or water . `` It somehow gives the impression that these are greedy people , '' Alvi said . `` But it 's not greed . It 's desperation . '' Hundreds of thousands of Pakistanis have acquired transmittable ailments such as acute watery diarrhea , scabies and respiratory infections . `` This is the desperation phase right now , '' Alvi said . `` I think a few weeks ... that 's when the diseases will get worse . '' Prime Minister Yousaf Raza Gilani has called a Tuesday meeting of local and national health officials as well as United Nations agencies and other international groups to address the mounting health crisis . The UN says it still needs about $ 200 million for aid . Kapadia said he wonders why some are n't donating as much to Pakistani flood relief as they have to previous natural disasters , such as the Haiti earthquake in January . `` Maybe it 's donor fatigue , '' he said . `` But that 's no excuse . '' Despite the heat , filth , disease and destruction , Alvi said he had no regrets about his decision to help . `` We could have stayed home and watched this happen on TV , '' he said . `` But someone has to take the next step . ''
Thousands of people are sleeping on muddy roads . The government has been unable to provide basic services such as water and electricity, which have become a major source of frustration for the people. Pakistan 's prime minister is set to meet with officials about the health crisis .