Charity Walks/Runs/Bike rides

The people who run events like the Avon Walk for Breast Cancer, or the Ride-the-Rockies are experts at taking care of a couple thousand people in tents for a week.
The government would be well served to ask them to help out in Louisiana, Mississippi and Alabama right now. They could provide immediate relief for the thousands there.
I know progress must be being made, but it seems amazing to me that after four days in the specific shelter that people were invited to use, there is no resources for human waste and only 1 nurse. Those people need some help now and while cash is great, what they need right now is water and a toilet or two.