The City of Austin Watershed Department is coordinating the Buy-Out Program.
See Link below:
https://austintexas.gov/department/onion-creek
These are only some of the Q&A available from the City of Austin Website:
You do not have to sell your home at this time for the Onion Creek buyouts. We will skip over property owners who do not want to sell until the project’s end, which may be years away. However, at the end of the project, we will return to those who did not want to sell. At that time, we will explain the eminent domain process. Please call Elaine Ververat 512-453-5501 for more information.
Appraisals are done by a third party independent appraisal company. There are various options if you do not agree with the appraisal. This will all be explained during the buyout process.
There are six priority areas in the Onion Creek buyout area. We are currently purchasing properties in Priority Area 3. We have limited City funding left for this project and without federal funding, it may take many years to reach Priority Area 6. We are continuing to work with the federal government to get federal funding for this project.
The City of Austin is partnering with the U.S. Army Corps of Engineers on this project. The Corps of Engineers helped study the situation, identify the solution and develop the priority areas. As planned, the bulk of the funding would come from the Corps of Engineers. The federal government has approved this project as part of the 2007 Water Resources Development Act. However, they have yet to appropriate funding.
Travis Austin Recovery Group, TARG 
How much more money is needed? I keep hearing about – not enough money to complete this buyout. The money is accumulating, yet very little action has occurred to get this project completed post haste! Residents lives remain at risk every time it rains! You have the money now do what you are saying you will do!
The city has approved the money to buy out all the houses that were a part of the Halloween Flooding 2013. They are the ones administering the individual buy outs. Here is their contact info: http://www.austintexas.gov/page/other-onion-creek-buyouts
City staff and HDR Engineering are working together on the real estate transactions for the buyouts.
Email the buyout team: http://www.austintexas.gov/email/onioncreekbuyouts
Alex Gale, HDR Engineering, 512-453-5501
Melinda Ruby, Project Manager, 512-453-5501
Pam Kearfott, Project Sponsor, 512-974-3361
For maintenance questions, please call 3-1-1.
Report suspicious activity to 911. For non-emergency security concerns, call Leticia Campa, APD District Representative, at 512-974-5490.