Yes, you absolutely do.
The real question is are you willing to do what charity:water does?
Most organization are not.
Here's what charity:water does that's different, according to npENGAGE, at So, You Want to Be like charity:water? They don't spend all their time and energy describing and explaining themselves. They focus on telling stories about their donors:
Most of us in America don't know what it's like to not have access to clean water, but by telling meaningful stories -- stories of those in need and stories of the supporters giving up their birthdays to help -- they help us relate to a community in Africa.
Please let that sink in a bit.
They aren't trying to raise funds by "educating" people about the problem of water in poverty areas. "