Press release from SMECO
HUGHESVILLE, Md. (Nov. 3, 2014)—Southern Maryland Electric Cooperative (SMECO) completed its Southern Maryland Reliability Project on November 3 when it energized the under-river portion of the 230,000-volt line that creates a transmission loop through the cooperative's service area.
According to Ken Capps, SMECO's Senior Vice President of Engineering and Operations and Chief Operating Officer, "The entire loop, which has been built in sections, has been a part of SMECO's vision since the early 1970s. In 1973, SMECO started the process of applying for the necessary permits, and the first section of the 230-kilovolt (kV) line from Ryceville to Lexington Park was energized in 1990. As the population and the demand for electricity increased, the necessity for a complete 230-kV loop increased."
Capps added, "We had a 69,000-volt line feeding Calvert County and lower St. Mary's for a number of years. When the submarine portion of that line failed on a very cold day in January 2005, the crucial importance of upgrading the line became obvious." SMECO's announcement for plans to upgrade the line to include 230,000-volt circuits officially began in 2008 at a meeting of the Calvert County commissioners on April 15 and St. Mary's County commissioners on April 22. After holding a series of open houses for the public and receiving customer-member comments about the project, the cooperative applied to the Maryland Public Service Commission for a Certificate of Public Convenience and Necessity (CPCN) on November 21, 2008, and the Commission granted the CPCN on September 9, 2009.
Capps listed some of the elements of the entire Southern Maryland Reliability Project: "During the course of this seven-year, $108 million project, we built switching stations in Aquasco and Sollers Wharf, and we expanded the switching station in Holland Cliff. To make efficient use of existing resources, we moved transformers from our Hawkins Gate and Hewitt Road stations and replaced them with new, larger transformers to increase capacity where it was needed most." The culmination of the project was crossing under the southern portion of the Patuxent River from the Navy Recreation Center in Solomons to Town Creek in St. Mary's County. During October, construction was completed and the line was tested before it was energized and put into service on November 3.
SMECO President and CEO Austin J. Slater, Jr., said, "We cannot overstate the importance of this project to the reliability of our system. Electric utilities are obligated to maintain the highest standard of reliable service and provide the most up-to-date technology to improve economic and operational efficiency. By completing this 230,000-volt loop through our service area, customer-members are assured of improved reliability." According to SMECO, although the project greatly enhances reliability for all of the cooperative's customers, it is vitally important to Calvert County and lower St. Mary's County, including Naval Air Station Patuxent River.
Capps highlighted the crowning achievement of the project: "We faced considerable challenges associated with engineering the river crossing. A year ago, we used a horizontal directional drilling technique to bore under the riverbed, and then pulled two bundles of five fusible PVC pipes through the bored holes. This was a first for the industry; no previous installations using fusible PVC come close to the length and complexity of this project. In October 2014, we completed the under-river crossing when we pulled cable through the conduit."
SMECO itemized the following construction highlights.
" 25.5 miles of PVC conduit and 6.9 miles of cable were used to complete the river crossing.
" 19,543 cubic yards of concrete were used for the foundations of 291 steel poles, replacing 430 poles used for the previous 69-kV line.
" 15.5 miles of roads were graded along the right-of-way and for construction access.
" 15 helicopter flights were used to install 181 of the 197 miles of conductor for 28 miles of overhead spans.
"We used existing right-of-way and we worked with customers along the route to minimize the impact of this line," Slater added. "We want to thank the elected officials who provided their support, as well as the regulatory agencies that worked with us on this project. When we started, we said we would do the Southern Maryland Reliability Project the right way, and we've received accolades from environmental and permitting agencies that held this project up as an excellent example, the standard to follow."
"Our previous peak demand record was set on January 17, 2009, at 848.8 megawatts (MW). In January, when the polar vortex brought us unusually cold weather, we surpassed that peak on six different days, and we set a new peak of 941.3 MW. We expect this new line to provide enough capacity to see us through the next 50 years," Slater said. He concluded, "I am immensely proud of the creative and gifted engineering, project management, and skilled execution exercised by our team in delivering this critical component of our electric system. And I am delighted that it was completed on time and under budget."
Source: SMECO