Erosion Hazard Zone Analysis
What You Need to Know About Erosion Hazard Zones
In Austin, any development near a creek or drainage way may require an erosion hazard zone (EHZ) analysis. This determines how close you can safely build without risking structural damage from erosion over time.
At Servant Engineering, we assess site-specific conditions to determine if your project falls within an EHZ. If it does, we provide a detailed report and recommendations to meet City of Austin regulations and keep your structure safe.
At Servant Engineering, we assess site-specific conditions to determine if your project falls within an EHZ. If it does, we provide a detailed report and recommendations to meet City of Austin regulations and keep your structure safe.
Do I Need an EHZ?
According to the Watershed Protection Ordinance adopted in October 2013, certain projects in Austin must include an Erosion Hazard Zone (EHZ) Analysis as part of the permitting process. This applies if your proposed construction or addition falls within:
- 100 feet of the centerline of a waterway with a drainage area of 64 acres or more
- 100 feet of the ordinary high water mark of the Colorado River downstream from Longhorn Dam
- An area with significant existing erosion
If your project meets any of these conditions, the City of Austin requires a report showing the potential extent of future erosion to ensure your development is safe and sustainable.
We can help you with a Level 1 Erosion Hazard Zone Analysis, which is often the first step in determining if further study is needed.
Source: Appendix E of City of Austin Drainage Criteria Manual