Houston Mayor Bill White says the biggest problem for emergency officials has been stranded motorists.
"We've gotten 500 calls in through the HEC Center on the 9-1-1 line for rescues. Most of those, the vast majority have been rescues from automobiles. I'd like tell the citizens of this community to be tuned to the news media and keep off some of these freeways."
The Houston Area Red Cross opened shelters for anyone whose home was flooded. Red Cross Spokeswoman Denise Bishop says people need to remember to bring certain items with them to the shelter.
"They need to bring bedding because sometimes there's cots and blankets and sometimes there's not. They need to make sure they bring their medications and especially prescriptions, they're not sure, they may end up spending the night, perhaps not. And any special needs items if it's older people or if people have special dietary needs, they need to keep that in mind. If they have young children and they need diapers or formula, please bring that."
The Southeast side of town experienced the worst of the flooding, with several feet of water in some homes. Harris County Judge Robert Eckels says the county's volunteer corps has also been activated to respond to the flooding.
"The first responder when an event like this happens, is the person who's there. And in this case, the volunteers come in and if it was a subdivision like Ponderosa, they would be there self-activated until the relief came in from either the fireboats, the rescue boats or the commissioner's precincts or public works or whoever was coming in. To the extent that their communities have been affected, they will have been activated."
Eckels says people should use common sense: don't drive into water that reaches over the curb, don't try to escape through rising water and do call 9-11 if you need rescue help. White says when you have this much rain on the streets you have to be prepared for any scenario.
"We live in Houston, Texas and you can't be surprised at flooding in Houston."
The State of Texas has swift water rescue teams on standby as well as high water vehicles ready to deploy if the city and county need assistance. Laurie Johnson Houston Public Radio News.