We look at a number of factors, including safety and cost. Some questions we ask are:
Keep monitoring the situation and get ready to potentially evacuate or move to the second floor or roof. The flooding may get much worse very fast. In Austin, our creeks can rise several feet in just a few minutes. Keep in mind that the road providing access to your home may become impassible before water enters your house. Leave before the road is flooded. Do not attempt to drive or walk through a flooded road.
If there’s time, the following steps can help limit damage:
• Turn off all utilities at the main power switch and close the main gas valve if evacuation appears necessary. • Move valuables, such as important papers, jewelry, and clothing to upper floors or higher elevations. • Fill bathtubs, sinks, and plastic soda bottles with clean water. Sanitize the sinks and tubs first by using bleach and rinsing. • Bring outdoor possessions, such as lawn furniture, grills, and trash cans inside, or tie them down securely.
There may be many reasons:
In our Master Plan, we identified enough projects to keep us busy until 2040. With so much need, we must carefully prioritize which projects get done first. For more information about how we prioritize projects, please see the answer to “How does the City decide which flooding situations to address first?”
Call 3-1-1. The Watershed Protection Department will send someone to document the flooding. This helps us understand where projects are necessary.
Call your homeowners insurance company and follow their instructions to file a claim and repair your house. A separate flood insurance policy is required to cover damages due to flooding. Here are some precautions:
Download this FEMA publication to find out more about repairing your home: Repairing Your Flooded Home.
Development is not allowed to cause additional flooding to other properties. Any time impervious cover is increased, there is the potential for increased stormwater runoff. Impervious cover includes roofs, parking lots, streets, driveways and other areas where the landscape cannot absorb rainfall. To combat this problem, the City of Austin requires all new developments to ensure that they will not adversely impact downstream properties. Developers are required to either provide on-site flow controls or pay fees for regional flood control projects.
A watershed is the area of land that drains to a particular location. In Austin, watersheds typically refer to the land draining to one of our larger creeks.
The 100-year storm is an event that has a 1% chance of occurring in any given year. To put that in perspective, during the span of a 30-year mortgage, there is a 26% chance that a 100-year event will occur.
The amount of rainfall necessary to produce a 100-year storm is partially dependent on the duration of the storm. If the rain falls over the course of 3 hours, it takes about 6 inches for it to be classified as a 100-year rainfall. But if those same 6 inches fall over the course of 3 days, it would be considered a much smaller rainfall event. The standard 100-year design storm for the City of Austin has a duration of 24-hours and produces a total rainfall of over 10 inches. To learn more about rainfall return periods in Austin, see section 2 of the Drainage Criteria Manual.
During a large storm, it is normal for the intensity to vary widely across the city. In September 2010, Tropical Storm Hermine produced rainfall totals equivalent to a 100-year storm over portions of the Bull Creek watershed. However, other areas of Austin did not experience as severe a storm. Keep in mind that even if a large storm has recently occurred, there is the same percent chance of an equally large storm occurring the following year.
Turn Around - Don’t Drown. Approximately 75% of flood fatalities occur in vehicles. Try to avoid driving during heavy rainfall. If you must drive, look for water over the road, avoid low water crossings, and turn around if a road is barricaded or if there is water over the roadway. Keep in mind that at night, during heavy storms, it may be difficult to see that a road is flooded.
There are many other dangers during a flood as well. In general, stay away from creeks and drainage infrastructure during rainfall.
There is more information about flood safety on our Flood Safety and Preparedness page.
In the right circumstances, almost any road can flood. The ones listed below are the ones that flood most frequently:
To find out if a road is flooded, check www.ATXfloods.com.