SCH Number 2014022059

Project Info

Title

Dredged Material Management Program - City of Alameda

Description

The primary objective of the project is to remove accumulated sediments from the lagoon system which has been causing the depth of surface water to decrease over the past few decades, potentially affecting the lagoon's water quality and wildlife habitats, and ability to function as a stormwater detention facility. The lagoon system is a component of a residential community and does not have a natural outflow. As a result, accumulating sediment and debris require removal through excavation and dredging. The City is now working with the Dredged Material Management Office (DMMO) to obtain the necessary approvals from state and federal agencies charged with ensuring water quality to begin dredging activities. Removal of these dredged materials and sediments will result in a positive impact to the water quality of the lagoons, as well as their habitat suitability for various wildlife species. The project will include dredging, excavation, hauling, and disposal activities. Dredging and excavation activities will be performed via mechanical/excavator dredge with placement of the material into barge mounted scows for dewatering. Dredging would include a compressor, crane, generator set, pump, and one additional piece of heavy equipment. During dredging, surface water will be removed along with sediment. The dredged material will be dewatered before removal so that temporary draw down of surface water would be limited to small quantities removed with dredged sediment. The majority of dewatering activities associated with the project will occur as the dredged material is brought from the bottom of the lagoons during removal. Dewatering activities are not expected to generate water requiring containment or disposal on land. Excess water brought up with the dredged material will be allowed to drain back into the lagoon at the priority area where the dredging occurred, before being loaded on the barge. The barge will be brought near shore and a land based excavator will remove the material and place into trucks to be hauled to a disposal site at Alameda Point.

3 documents in project