- Published on Wednesday, 01 May 2013 22:54
- Written by Super User
The Town of Carolina Beach is moving forward with a project to repair a secondary sewer force main line and other utility infrastructure.
By WILLARD KILLOUGH III
CAROLINA BEACH - The Carolina Beach Town Council will discuss moving forward on a project to replace a sewer force-main at their upcoming Tuesday May 14th meeting.
On April 24th, Brian Cox of Engineering Services - the firm contracted by the Town - explained, "Per our conversation this morning, I wanted to provide you with some of our concerns about the sewer collection system, pump stations and force mains. Pump Stations #1, 2, 3, 5 and 6 pump to a common primary force main that flows directly to the" Town's wastewater treatment plant off Dow Road.
Pump station #1 is located near the Boardwalk on Raleigh Avenue and was recently rebuilt due to age.
Cox explained, "There is also a secondary force main that is used during heavy rain events that generate a high flow to the pump stations. The original design for pump station #1 was to use the secondary force main on a full time basis. The condition of the secondary force main was determined to be in poor shape and we recommend that its use be limited to emergency situations. Having only the primary force main available for full time use is placing a lot of pressure and wear on the pump stations connected to this line."
During heavy rain events, water enters the sewer system placing a higher demand on pumps and lines. This is called inflow and infiltration. In the early 2000's the Town replaced sewer lines on Carolina Beach Avenue North and Canal Drive to reduce infiltration of water from rain and tidal flooding to reduce the burden on the wastewater treatment plant.
Cox explained, "This increase in wear requires more frequent replacement of parts and increased chance of failure. During heavy rain events, with all of the connecting pump stations running and competing for space, the primary force main is maxed out. Opening the secondary force main has proven to alleviate the pressure on the system, but the secondary force cannot be relied on for extended service. If there is a failure from overuse of the secondary force main, then the primary line will become the only means to pump the flow."
He explained, "Based on our Inflow and Infiltration Study provided to you in November 2012, the collection system in the older residential areas, that flow to these pump stations, are in need of repair. These areas were reviewed by video taping the sewer lines to locate and identify the issues. The identified areas in need of repair contribute inflow and infiltration to the pump stations and force main."
Cox wrote to Public Utilities Director Gene Gurganious that, "We are concerned that delaying the repair and/or replacement of the secondary force main increases the chance of a failure, while placing increased operation and maintenance costs on the system."
Cox explained it would take around nine and a half months to complete a survey, engineering plans, obtaining permits, advertising for bids from contractors, awarding a bid and getting approval from the Local Government Commission for project financing. 90 days of that period would be required for construction.
He explained, "We recommend beginning the survey and design work for the force main improvements as soon as possible, while at the same time moving forward with the survey and design work for the sanitary sewer collection system and water line improvements. These projects can be bid and constructed at separate times. It is also recommended to begin the survey and design work immediately in order to meet the next funding cycle in September 2013."
He explained that when seeking grant funding from the State through the Drinking Water State Revolving Fund (DWSRF) and Clean Water State Revolving Fund (CWSRF), applications that are submitted with designed and permitted projects receive a priority status.
On Tuesday April 30, Councilman Steve Shuttleworth said the Council gave direction to department heads at their April 26, budget meeting to move forward on addressing the secondary force main. He said, "It's at a critical stage and almost an emergency" and is expected to cost around $900,000. He said Town Manager Bruce Shell will bring a recommendation at their May 14th, meeting on how to proceed.
Shuttleworth said the Council is also pursuing replacement of water and sewer lines in the older residential areas of Town from Lake Park Blvd west to Dow Road.
He said the current hope is to move forward with planning and start work following the summer season.
The secondary force main is part of the first phase of a three-phase project recommended in a study completed in November 2012.
The first phase would address 29,000 linear feet of galvanized and cast iron water lines in the older sections of Town and replace them with newer plastic PVC pipes to improve water quality. Also, rehabilitating 34,000 linear feet of sanitary sewer lines. It also included the 6,000 linear foot secondary sewer force main for pump station number one.
All in total, that phase is estimated to cost approximately $8.7 million dollars for engineering, permits and construction.
The other two phases call for a 1.5 million gallon ground level water storage tank, pumps, piping and a new well as well as installing a reverse osmosis plant, an Aquifer Storage and Recovery (ASR) well, pumps and piping. An ASR well treats water and injects it into the aquifer underground to be pumped out again when demand is higher in the busy summer months. I can also help prevent saltwater intrusion into the 14 wells located throughout Town.
The total cost for those two phases combined is estimated at $6,052,059.