From
Romin Khavari
Title
Resolution establishing a policy concerning Creek Erosion and other Drainage Policy Updates
Presenter
Romin Khavari, City Engineer and Stephanie Griffin, Storm Water Utility Manager
Recommended Action
Approve
Analysis
Following the floods of 2015 that caused erosion of several creeks in the City of Grand Prairie, City Staff made presentations to the Development, the Public Safety Health and Environment, and the Finance and Government Committees about erosion and other drainage problems related to waterways. On April 5, 2016 the City Council adopted resolution 4812-2016 to address these issues.
A major portion of the policy deals with a voluntary buy-out consideration for private habitable structures that are in eminent danger due to erosion based on engineering criteria. Since the adoption of this resolution, concern has been raised about the specific provision in the policy for the City to provide for relocation expenses as prescribed in the Uniform Relocation Act.
Upon further investigation with other entities providing such assistance to their citizens, and in discussion with our city attorney’s office, the provision of the Uniform Relocation Act does not apply to the property owner because this is a voluntary city buy-out program. Therefore, the policy is being revised and updated to make this revision noted in bold font below:
Erosion and/or flooding problems on private property will be investigated on a case-by-case basis. The City will focus on improvements to the waterways that will result in a general public benefit, such as lowering erosive velocities and increasing flow capacities in proximate streams for the general prevention of erosion and flooding and to include those improvements that are required to protect public city utilities such as Water, Wastewater and Drainage facilities.
Remedy of private property issues, such as flooding due to lot-to-lot drainage (no involvement of City property); and construction projects to protect specific private property due to proximate stream erosion will not be undertaken by the City unless a general public benefit or public safety concern can be demonstrated. If there exists an eminent danger to private habitable structures due to erosion based on engineering criteria, voluntary buy-out consideration may be approved by the City Council.
City will encourage the property owners to purchase of flood insurance for habitable structures adjacent to rivers and creeks.
Individual projects will be evaluated and prioritized based on available funding.
The following general engineering criteria shall be followed to help determine if only the habitable structure (excluding, fences, sheds, swimming pools, etc.) is in eminent danger:
1. Evident head scarp associated with a rotational slide is within three feet or less from the foundation to include the following:
a. Development of tension cracks on the slope face as well as on the top
b. Top of slope dropping leaving vertical scarp
c. Toe of slope bulging upward
2. Development of “cut bank” less than 15 feet where the top of the bank is located closer to the foundation than the height of the bank (H) plus 5 feet (H+5’).
3. For cut banks 15 feet and higher, the foundation should be a minimum distance of 1.5 times the height of the bank (H).
4. Sudden lateral and or leaning movement of site paving, retaining walls, fences or trees indicating sliding or rotation failure within three feet of the foundation.
5. Sudden foundation movement down or laterally towards a slope
6. Rupturing of utilities shortly after flood events, especially where the rupture is near the foundation or between the foundation and the failing slope.
7. Development of multiple head scarps indicating rapid progressive failure.
8. Any exposed vertical cut banks in weathered or unweathered shale where bedding planes dip towards the slope.
If the habitable structure satisfies these engineering criteria, the City will hire a geotechnical engineer registered in the State of Texas for a more detailed evaluation based on field bore samples.
The following general voluntary buy-out procedure shall be followed:
1. City will obtain an appraisal to determine fair market value and provide opportunity for a counter offer based on the owner hiring and paying for another appraisal.
2. City will provide for relocation expenses as prescribed in the Uniform Relocation Act. The parties recognize that this is a voluntary buy-out with the property owner and not for a City project, so relocation expenses will not be provided.
3. City will negotiate accordingly to arrive at an amicable agreement to present to the City Council for consideration.
4. The property owner shall obtain a flood insurance policy for the habitable structure under consideration to be effective and in force during the duration of the voluntary buy-out process in case of catastrophic failure. Documentation shall be provided by the property owner to the City.
Upon the successful voluntary buy-out, the city will remove the habitable structure and any improvements as deemed necessary and dedicate and maintain the property as a Storm Water Management Area.
This revised Policy will update and replace the previous Policy (Resolution No. 4812-2016) in its entirety.
Financial Consideration
Increase to the Storm Water Utility rates to pay for the public benefit improvement projects and to include the voluntary buy-outs.
Body
A RESOLUTION OF THE CITY OF GRAND PRAIRIE, TEXAS, ESTABLISHING A POLICY CONCERNING EROSION AND OTHER DRAINAGE PROBLEMS RELATING TO WATERWAYS
WHEREAS, the City Council has determined that Erosion problems along the Trinity River and Creeks in the city are of concern to the City.
NOW, THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF GRAND PRAIRIE, TEXAS:
SECTION 1. That it is hereby determined to be in the best interests of the City of Grand Prairie, Texas and its inhabitants to adopt the following drainage policy:
Erosion and/or flooding problems on private property will be investigated on a case-by-case basis. The City will focus on improvements to the waterways that will result in a general public benefit, such as lowering erosive velocities and increasing flow capacities in proximate streams for the general prevention of erosion and flooding and to include those improvements that are required to protect public City Utilities such as Water, Wastewater and Drainage facilities.
Remedy of private property issues, such as flooding due to lot-to-lot drainage (no involvement of City property); and construction projects to protect specific private property due to proximate stream erosion; will not be undertaken by the City unless a general public benefit or public safety concern can be demonstrated, eminent danger to private habitable structures due to erosion based on engineering criteria for voluntary buy-out consideration and the undertaking of such are subject to approval by the City Council.
City will encourage the property owners to purchase of flood insurance for habitable structures adjacent to rivers and creeks.
Individual projects will be evaluated and prioritized based on available funding.
The following general engineering criteria shall be followed to help determine if only the Habitable structure (excluding, fences, Sheds, Swimming pools, etc.) is in eminent danger:
1. Evident head scarp associated with a rotational slide is within three feet or less from the foundation to include the following:
a. Development of tension cracks on the slope face as well as on the top Top of slope dropping leaving vertical scarp
c. Toe of slope bulging upward
2. Development of “cut bank” less than 15 feet where the top of the bank is located closer to the foundation than the height of the bank (H) plus 5 feet (H+5’).
3. For cut banks 15 feet and higher, the foundation should be a minimum distance of 1.5 times the height of the bank (H).
4. Sudden lateral and or leaning movement of site paving, retaining walls, fences or trees indicating sliding or rotation failure within three feet of the foundation.
5. Sudden foundation movement down or laterally towards a slope
6. Rupturing of utilities shortly after flood events, especially where the rupture is near the foundation or between the foundation and the failing slope.
7. Development of multiple head scarps indicating rapid progressive failure.
8. Any exposed vertical cut banks in weathered or unweathered shale where bedding planes dip towards the slope.
If the habitable structure satisfies these engineering criteria, the City will hire a geotechnical engineer registered in the State of Texas for a more detailed evaluation based on field bore samples.
The following general voluntary buy-out procedure shall be followed:
1. City will obtain an appraisal to determine fair market value and provide opportunity for a counter offer based on the owner hiring and paying for another appraisal.
2. The parties recognize that this is a voluntary buy-out with the property owner and not for a City project, so relocation expenses will not be provided.
3. City will negotiate accordingly to arrive at an amicable agreement to present to the City Council for consideration.
4. The property owner shall obtain a flood insurance policy for the habitable structure under consideration to be effective and in force during the duration of the voluntary buy-out process in case of catastrophic failure. Documentation shall be provided by the property owner to the City.
Upon the successful voluntary buy-out, the city will remove the habitable structure and any improvements as deemed necessary and dedicate and maintain the property as a Storm Water Management Area.
SECTION 2. That this new Policy will update and replace the previous Policy (Resolution No, 3919) in its entirety and this resolution shall become effective immediately upon its passage and approval.
PASSED AND APPROVED BY THE CITY COUNCIL OF THE CITY OF GRAND PRAIRIE, TEXAS, ON THIS THE 6TH DAY OF SEPTEMBER, 2016.