Providence Lake Borgne Oyster Assessment
April 2023 | Tennessee Gas Pipeline Company, LLC is proposing to replace a 529E-101 6-inch valve on an existing pipeline located in Lake Borgne in St. Bernard Parish, LA
Tennessee Gas Pipeline Company, LLC is proposing to replace a 529E-101 6-inch valve on an existing pipeline located in Lake Borgne in St. Bernard Parish, La. The company wants to avoid damaging any oyster resources along their valve replacement site. In support of this, ENCOS, Inc. (ENCOS) was contacted to perform a water bottom assessment for sampling within the 500 feet buffered area surrounding the temporary workspace.
All sampling was conducted using a 23-foot Majek Illusion workboat drawing approximately 9 inches of water. Poling points were identified using a Trimble R2 GNSS Receiver. The bottom was sounded utilizing a 20-foot long carbon fiber pole at 30 feet intervals along north/south transects. The transects, spaced 100 feet apart, covered the bottom of the water body within the 500 feet buffer of the proposed work. The bottom type was determined in real time and entered in a field computer on site.
Two 3-minute dredge tows were conducted using a 2-foot commercial oyster dredge to verify poling data of soft mud, moderately firm mud, and firm mud or sand. The results of the poling did nor reveal any areas of exposed shell that indicate a reef complex; therefore no dive samples were conducted.