Project Background
ATSER supported Harris County Engineer and CivilTech (a division of Woolpert) on the Ralston Acres Subdivision Drainage Improvements project, addressing critical flooding issues in the area. This $761,000 initiative involved designing and constructing two wet-bottom detention ponds, one south of channel P-177-00-00 and the other north of channel P-115-00-00.
The Problem
Flooding concerns in the Ralston Acres Subdivision required effective drainage solutions. Initial designs for dry-bottom detention ponds were adjusted mid-project to accommodate wet-bottom ponds, necessitating additional geotechnical investigations.
The Goal
To provide accurate geotechnical data and recommendations for the design and construction of the detention ponds while maintaining flexibility for mid-project design changes.
The Solution
ATSER delivered a comprehensive geotechnical investigation, including:
Exploratory Borings
- Drilled 12 borings (three at 10 feet, nine at 20 feet) to collect soil samples from critical locations.
Groundwater Monitoring
- Installed two temporary piezometers to assess groundwater levels and support hydrological evaluations.
Laboratory Testing
- Conducted in-depth soil analysis, including moisture content, Atterberg limits, grain size distribution, unconfined compressive strength, and specialized tests like the Pinhole and Crumb Tests for flexible pavement analysis on John Ralston Road.
Geotechnical Engineering Analysis and Recommendations:
- Provided tailored recommendations for detention pond construction, adhering to Harris County Flood Control District (HCFCD) PGPM guidelines and ensuring effective site drainage.
Results
ATSER’s adaptability to project changes enabled the successful completion of wet-bottom detention ponds that aligned with hydrological needs and addressed local flooding concerns. By refining soil boring depths and adjusting analysis mid-project, ATSER ensured the recommendations were precise and effective.