Geocon conducted a geotechnical investigation at Lower Turtle Pond in the La Honda Creek Open Space Preserve, assessing the soil integrity of the pond berm and underlying subgrade. The investigation aimed to evaluate the soil composition and provide recommendations for mitigating potential distress or failures in the pond area. 

Minor cracking along the berm’s crest was observed, but no signs of instability or seepage were noted. Slope stability and seepage analyses confirmed the berm’s stability under static and seismic conditions. To prevent further cracking, Geocon recommended adding a 12-inch layer of low-expansive soil along the berm top and suggested erosion control measures at the spillway. 

Geocon also provided geotechnical testing and observation services during spillway repair construction, which included grading and placing imported fill to reduce the risk of desiccation cracking from expansive soils. 

By offering ongoing support during spillway repairs, Geocon played a key role in ensuring that the preserve remained a safe and thriving natural resource, ultimately benefiting both the local ecosystem and the community who value this public space.  

Client
Midpeninsula Regional Open Space District

Services
Geotechnical Engineering

Geocon Leader
Shane Rodacker, GE