The project consists of a new 80-foot single-span steel beam bridge structure supported on deep foundations, and two stormwater management facilities, in a residential development.  Geotechnical engineering services consisted of test borings, rock coring, laboratory testing, geotechnical evaluation and preparation of a geotechnical report for the proposed bridge construction.  The subsurface investigation included drilling 10 test borings to depths ranging from 15 feet to 46 feet with an ATV-mounted drill rig equipped with diamond core drilling equipment to secure rock core samples. 

The laboratory testing program included moisture content, compaction, sieve analysis and Atterberg limits for soil classification.  The report included subsurface information, characterization of residual soils, weathered rock, and rock; laboratory test results, recommendations for design of drilled pier foundations, and stormwater management facilities.  Construction phase services included inspection of drilled pier foundations, concrete abutments, and bridge superstructure construction.  As-built inspection services were provided for the stormwater management facility construction.

• Evaluation and recommendations regarding drilled pier foundations founded in rock and weathered rock, with minimal differential settlement.  Recommendations were provided for a 100-ton allowable drilled pier capacity.
• Inspection of drilled pier construction to verify that the drilled piers were extended into weathered rock capable of supporting the design loads.