by Mike Fernandez

Altamonte Springs, FL - Central Florida Underground, Inc. of Altamonte Springs, Florida has completed the installation of a storm drain sedimentation baffle box at the City’s Little Wekiva River location. The box will serve as a filter for collecting sediments and floating debris from stormwater before draining into the river.

Working conditions were very tight with the site located on a narrow residential street. The project required the installation of a cast in place baffle box measuring 28 feet long x 20 feet wide x 14 feet high for a 60 inch outfall line. Due to the limited work space a Komatsu model 200 was chosen for the excavation and installation of the shoring system. Vibration during the installation process had to be kept to a minimum as the surrounding concrete block houses were prone to structural damage. Florida’s typical sandy soil and an 8-10 ft. water table added to the challenging project.

Efficiency Shoring Systems of Florida, (a division of Efficiency Production, Inc.) located in Tampa, was consulted to provide a shoring solution for the installation of the large structure. Working closely with CFU’s personnel, Efficiency’s Shoring Specialists & Engineers determined that the project required a specialized shoring design. A combination of Efficiency’s Slide Rail and Shore-Trak systems was chosen for their unique capabilities. The system was designed to maintain stability of poor soil during excavation. The Slide Rail panels could be easily positioned in a confined area. It’s innovative post and panel design would also reduce binding and vibration during installation.

Efficiency’s Bill Cassels, Byron Adams, and Doug Austin provided on-site technical and product support for the installation of the shoring system. On site along with CFU and Efficiency was the City of Altamonte Springs representative Roger Densberger, and Professional Engineering Consultants, Inc.’s representative Greg Teague.

The site was dewatered with wellpoints and a vacuum pump before proceeding. The shoring for the structure was accomplished by first installing a combination of the Shore Trak guideframes and vertical panels along with Slide Rail posts and horizontal panels around the perimeter of the pit. As excavation continued additional horizontal Slide Rail panels were installed until final grade was reached. Upon completion the shored pit measured 38 feet wide x 42 feet long x 17 feet deep.

CFU’s project manager, Fred Spielmann, stated "The Slide Rail System was the best choice! We’ve tried others in the past but when we used Efficiency’s system we were sold! It went in faster than sheeting and it minimized the vibration to the surrounding houses."

CFU employs a full time Safety Director and has an excellent safety record. Their primary work consists of sewer, water, and storm drainage, conduit, and horizontal boring throughout Central Florida.