You may have been directed here for information about the floods in Jeddah of 2011. I have stopped actively researching how to help the flood victims, but you can find all the information I did find here.

#JeddahRain Volunteering (OUTDATED)

Volunteering at Friends of Jeddah Parks
- Practical physical help
- Bus transport for volunteers
Meeting at: Faisal's Sports Park, (map)
Muḥammad Al Shihrī: 054 116 9698
Mayan Al Zawāwī: 056 704 5302

Youth Initiative Group
The website says to go here and register for the Jeddah Rains volunteering.
Their Facebook group has comprehensive updates received via message about what volunteering opportunities there are.