A. ROLL CALL
Members Present: Richard Aries, Joseph Carino, Robert Dickinson, Carol Fletterick, and William Vees
Alternates Present: Ed Havens, Jr.
Alternates Absent: Richard Siedman
Staff Present: C. Fred Shaw, Superintendent of Pollution Control
Ether A. Diaz, Recording Secretary
Others Present: Don Antaya, WPCA
Dennis A. Dievert, Jr., P.E., Wright-Pierce
Chairman Richard Aries called the meeting to order at 7:00 p.m. The following actions were taken during the February 7, 2012 Regular Meeting of the Water Pollution Control Authority (WPCA).
B. ACCEPTANCE OF MINUTES OF PREVIOUS MEETINGS
1. January 18, 2012, Special Meeting
Motion was made to accept the minutes of the January 18, 2012 Special Meeting as presented.
The motion was made by Mr. Ed Havens, Jr.
The motion was seconded by Ms. Carol Fletterick
The motion carried unanimously
C. NEW BUSINESS
1. Clark Street Pump Station Force Main Evaluation – (Report from Wright-Pierce).
A copy of the Clark Street Pump Station Force Main Evaluation Piping Report was included with the meeting Agenda for review. Mr. Dennis Dievert, Jr., P.E. from Wright-Pierce Engineers was in attendance to present the findings of the Clark Street Pump Station Force Main Evaluation. (See Exhibit A).
Mr. Dievert presented a brief overview of the project. He explained that the Town of South Windsor Water Pollution Control Facility (WPCF) staff has expressed concern about what the current risk of the pipe is and what that means to the Town in terms of that pipe line as a liability instead of an asset. The purpose of the force main evaluation is to identify potential areas of failure through non-destructive testing methods and to recommend implementation plans to avoid any future potential failures within the pipe line.
The Clark Street Pump Station and its force main were originally constructed between 1971 and 1973, with an upgrade to the pump station occurring in 2003.
Prior to that, there were water hammer issues at the station. When the Clark Street pump station was upgraded in 2003, a permanent surge tank was installed to eliminate the water hammer problem. In addition, a bypass connection was installed to allow for complete bypassing of the pump station in the event of an emergency.
Mr. Fred Shaw asked Mr. Dennis Dievert to explain what the bypass entails. Mr. Dievert responded that according to the Town’s Emergency Operation Plan (EOP), the bypass connection entails piping configurations to isolate from wet well. He explained that Godwin pump would be placed on top of the wet well, and pump waste water from the wet well to a bypass vault connected to the force main. It will allow bypassing the station.
Mr. Dievert also explained, that there is a contingency plan in place within the Town’s EOP to draw additional waste water using vacuum trucks to insure that flow is maintained during peak conditions or during the high flows to avoid an over flow. Mr. Shaw also explained that the WPCF staff is concerned even with the EOP that these measures would be insufficient to handle the flow.
During this evaluation, the following scope of services was performed:
RISK ASSESSMENT: A risk assessment was performed in accordance with the American Water Works Association (AWWA) guidelines as outlined in the 2008 Failure of Prestressed Concrete Cylinder Pipe document. A short form risk (qualitative) assessment was included in the AWWA document and was utilized to evaluate the Clark Street pump station force main. One of the questions was whether or not the pipeline was constructed prior to 1964 or after 1992. The pipeline was constructed in 1973, therefore, from this document it is known that the year in which the Clark Street force main pipe was manufactured is within a category (between 1972 and 1978) where there have been a wide range and percentage of reported PCCP failures identifying this force main pipe to be at a high risk for failure. Mr. Dievert
explained that an answer “no” to these questions scores “-1”. The total assessment score for the Clark Street pump station force main is “-3”. A negative score on the assessment suggests that further assessment of the pipeline is necessary. Based on this score, a formal condition assessment of the pipeline including internal and external inspection methods was warranted and was subsequently conducted.
CONDITION ASSESSMENT: An internal, non-destructive inspection was performed, utilizing the “SmartBall” technology by Pure Technologies. The SmartBall is used to detect acoustics associated with leaks or pockets of trapped gas in pipes. Any pockets of trapped gas in pipes could contribute to deterioration of the pipe at that particular point. The SmartBall was inserted into the check valve and was deployed through the force main in “live” flow; the SmartBall was retrieved just downstream of the discharge manhole at the intersection of Chapel Road and Clark Street. The review of the results by Pure Technologies concluded that there were no acoustic parameters that resembled leaks or pockets of trapped gas.
Continuing with the Condition Assessment, an External Testing and Evaluation of force main was performed. This testing was conducted at three different locations. To determined those three locations Wright-Pierce hired Corr-Tech which measured the soil resistivity in 500 foot intervals along the force main to confirm where external corrosion would be most likely to occur. Deterioration is expected to be rapid and relatively severe in soils below 1,000 ohm-cm. Using the 1,000 ohm-cm as a reference point, the two readings that were the lowest and very closed to a 1,000 ohm-cm were selected; the third location chosen was the last 80-feet of the pipe on Clark Street. This was determined to be in poor condition.
In referring to the Power Point Presentation (Exhibit A), Mr. Joseph Carino asked Mr. Dievert to explain what a discharge manhole is. Mr. Dievert responded that is an internal manhole located in the middle of the intersection of Clark Street and Chapel Road where the pipe dumps into the gravity system from the pump station.
Wright-Pierce hired J&H Slater Construction Company to conduct the excavation and expose the pipe. They exposed the pipe from the 9 o’clock to 3 o’clock positions to assess the condition of the force main. They tested the concrete of the force main for pH testing; and a hardness testing of the pipe was also performed. Also, based on their knowledge and experience, they used an ultrasonic device over the exterior of the pipe to measure the thickness of the pipe concrete coating. The external inspections of the three exposed force main locations indicated that the pipe is in deteriorating condition (refer to pictures on the Power Point Presentation – Exhibit A). Variations in the thickness of the concrete were found; approximately ¼” of cement loss was observed on the exterior of the pipe, which can start to corrode and lead to a potential pipe failure.
Additional Field Investigations were performed on the last 80 feet of the force main from the discharge manhole heading towards the Clark Street pump station. This section of pipe was inspected using a closed circuit TV. This revealed that there were several areas where the interior concrete layer was corroded and the steel cylinder was exposed. Also, this has indicated significant corrosion damage where the pipe is not flowing “full”. Chairman Aries asked if this is due to gases in the pipe. Mr. Dennis Dievert responded that is similar to what was happening on the gravity lines of Chapel Road where the pipe collapse. This is where hydrogen sulfite gases come out of solution and cause the formation of sulfuric acid on the concrete which leads to pipe corrosion.
In reviewing the alternative of bypassing the pumping during emergency situations, Wright-Pierce reviewed the Town of South Windsor Emergency Operation Plan (EOP) for the pump station. The EOP was last updated on March 2011 and includes emergency procedures; contractor and vendor contact information and pump station specific information. The EOP was reviewed for the Clark Street pump station and it was found to be up to date, complete and comprehensive. Mr. Dievert explained that with that plan in place the bypass of the pump station is possible; however, keeping up with peak flows will be a challenge. In the event of a force main break or failure, the vacuum trucks will be required to keep up with peak flows.
The EOP identifies available “draw” and “dump” sites for the supplemental vacuum trucks; these same sites would also be used for bypass pumping of the force main pipe until the pipe can be repaired. Mr. Dievert expressed that he does not think there is enough money or trucks or sites to draw from to keep up with that flow.
Mr. Dievert concluded that there is no way to bypass the force main pipe other than trying to keep up with the vacuum trucks or installing a temporary pipe (fused HDPE or PVC) along the top of the roadway from the pump station to the discharge manhole. This will take about two weeks to set up and install such a system; therefore, vacuum trucks are the only alternative available during this time. The installation of the temporary line is both time consuming and expensive.
In reviewing the alternatives for bypassing the pump station, three major corrections or rehabilitation methods are considered. One alternative for bypassing the pump station is to install a new pipe in at the same trench. One disadvantage of this alternative is that a full bypass of that line would be required during construction and that there would be extensive pavement restoration. Another disadvantage would be that there would be no permanent force main bypass in place.
The second alternative involves installing a new pipe parallel in the same trench; basically, running a new line all the way down Clark Street. One advantage of this is that the existing pipe can be used as a bypass; two lines will be available for pumping the flow from the Clark Street pump station. However, is very expensive, but is actually cheaper to install a new pipe than to do the relining or slip lining of the existing pipe.
The third alternative was slip-lining the existing pipe would have similar advantages and disadvantages as the first alternative involving installing a new pipe in the same trench. Bypass during construction would be required, there will be no permanent force main bypass and there would be a reduction in pipe diameter of the hydraulic capacity of that existing line.
Based on the evaluation, it is recommended to install sewer manhole and replace the last 80-feet of force main with PVC gravity piping. This has been already approved by the Authority as part of the Phase 1 Rehabilitation Project. It was recommended to do Phase 2 within 10 to 15 years. The dollar value presented in the amount of $2.5 to $3.9 million. The $2.5 million is assuming that the existing pipe line can be reused as a secondary means of bypass with no modifications. The $3.9 million is assuming that that pipe would need to be rehabilitated or relined; this will be over the course of the next 20 years. With nothing else to report, Mr. Dievert opened the floor for questions.
Mr. William Vees asked Mr. Dievert if he felt comfortable with the current EOP of the Town. Mr. Dievert responded that for the pump stations it is more than sufficient.
Mr. William Vees also asked if the EOP addresses a force main failure. Mr. Dievert responded that it does address a force main failure because it does include a list of on call excavation contractors for emergency repairs of the pipe. However, as far as bypassing the force main it only refers to vacuum trucks. He recommended adding to the EOP that in an event of a force main failure to have the on call contractor install a temporary 5800 feet of pipe. Hence, he believes that the repair could be made prior to setting up and installing a temporary pipe (fused HDPE or PVC).
Mr. William Vees also asked what the risk of a force main failure is based on the analysis that has been done. Mr. Dievert responded that is in the middle based upon the range described in AWWA; is based upon the facts that it was constructed during that time period where there is a history of failures, also, the fact that it is a pressure line and there was water hammer issues in the past which could have weaken the pipe in some degree. And then there is the unknown, the fact that there is no knowledge of who exactly manufactured the pipe and there are no records of its installation and whether it was installed properly, that is a risk in itself.
Chairman Richard Aries expressed concern over the overlay involved in figuring out all the expenses. Mr. Dievert reported that based on the evaluation, high potential costs and overall risk of potential failure, the recommendations are incorporated into the Town’s current Capital Improvements Plan (CIP).
William Vees asked how many homes and businesses will be impacted should there be a force main failure. Mr. Fred Shaw responded it will be probably the whole eastern ½ of the Town.
Chairman Aries asked what the liability is for the Town in regards to sewage that goes in to someone home due to failure; does the Town have liability for that. Mr. Shaw responded that the Town’s insurance company does not pay except if the Town has been negligent. If the Town responds quickly and appropriately, the Town is not negligent; and therefore, has no liability.
Mr. Joseph Carino asked what is so unique of the last 80 feet that requires it to be done first. Mr. Dievert responded that that portion of the pipe is not under full pressure; and therefore, the pipe corrosion is more extensive. Based on the investigation that was conducted, that pipe is at greater risk of failure.
Mr. Ed Havens, Jr. asked if the pipe will be replaced with reinforced concrete pipe or PVC. Mr. Dievert responded that will be with PVC. He explained that a manhole will be placed on top of the force main pipe and then it will be PVC gravity out from there to Chapel Road. During the connection, to minimize bypassing pump for the day, an additional manhole will be installed.
Mr. William Vees asked in regards to the concrete compression drains at the Clark Street pump station force main ranging from 1,068 to 3,972 psi. He asked what causes the softening of the concrete. Mr. Dievert responded that is due to hydrogen sulfide and the pH of the concrete. He explained that a pH of a normal concrete is 12 or 13; however, the pH of the concrete of the existing pipe was down to 8 or 9. The decreasing of the pH is due to what’s in the ground water and what’s in the soil surrounding the pipe; suggestive that the water and soil are reactive and contributing to the corrosion of the concrete pipe.
2. Request to use two private meters at The Promenade Shops at Evergreen Walk on Buckland Road – (Approval)
Mr. Shaw reported that he received a letter from the applicant requesting approval to install two private meters for the purposes of measuring water that doesn’t go into the sewer system (see Exhibit B). Mr. Shaw has inspected the facility and looked at the underground pipes and at the two locations where the two flow meters were installed. The two meters were installed by the CT Water Company for the lawn sprinkler system. And then later in the fall, the water company removes the meters and
drains the line. Mr. Shaw expressed that he was satisfied with the meters that are in place; they are in good locations. The applicant has been informed of the program requirements.
Motion was made to approve the use of two private meters at The Promenade Shops at Evergreen Walk on Buckland Road, for the purpose of measuring lawn sprinkler water that doesn’t go into the sewer system. This approval is subject to meeting all Town regulations and appropriate technical specifications relating to sanitary sewer construction. The applicant needs to read these meters not less than once a month, have the meters maintained, make sure that they are accurately recording flow; the applicant shall allow the Town staff the opportunity to come in and check that the meters are in good operating order; and annual reports of meter readings are to be submitted to the Town each year in January and a written meter report on company letterhead for the proceeding calendar year.
The motion was made by Mr. Robert Dickinson
The motion was seconded by Mr. William Vees
The motion carried unanimously
D. COMMUNICATIONS AND REPORTS
1. Treatment Plant Upgrade (Progress Report)
Mr. Fred Shaw reported that this project is moving along; the contractor is in the process of completing the punch list at this time. Some of the work cannot be completed until the warmer weather comes.
Mr. Shaw informed the Authority that the Treatment Plant Upgrade is scheduled to be completed this spring. The Town is scheduled to make its first payment next year in September of 2013; this includes the 1/20th payment of about $1.7 million; The debt service will then be repaid in subsequent months there after. However, the Town has the opportunity to complete the permanent loan obligation agreement with the State and start making payments for the treatment plant sooner; in October 2012 instead of waiting until September 2013. By paying the loan earlier in October, the Town will avoid accruing monthly interest between the time of project completion and September 30, 2013. Also, the Town would be able to avoid having to make the 1/20th payment upfront. This will involve some discussion
with Town Council concerning how the debt service will be paid for by the Town and how it would be provided for in the budget for fiscal year 2012/2013.
From previous discussions, it was decided that the WPCA would pay the 1/20th payment through sewer user charges and on such was planning to meet this obligation by September 2013. The Town Council in the General Government Budget would pay for the debt service beginning in September 2013. A copy of the payment summary schedule and an explanation from the State concerning the current obligation was provided (see Exhibit C and D). The Town currently has a signed Interim Financial Obligation (IFO); in that obligation there is a language that allows the Authority to start making payments sooner. Mr. Shaw can provide the Authority with “what if’s” analysis to try to get a better idea of what these costs will be. Should the Authority decides to go with this option, the Authority will need to sign the Permanent Loan Obligation (PLO) agreement before the completion date (September 2012) of the Treatment Plant project, and begin repayment in October of this calendar year, for next
fiscal year.
Mr. Fred Shaw will provide more information to the Authority.
2. Dry Pit Pump Station Upgrade (Progress Report)
Mr. Shaw reported that this project is progressing. The substantial completion date of this project is August 2012, which involves the upgrade of the last three pump stations in Town. The pump station will be operating as a new station by this date, but there will be a punch list to complete in the months to follow.
3. South Windsor Plan of Conservation and Development (Invitation from the SW Planning and Zoning Commission)
Chairman Richard Aries reported that the Authority received an invitation from the South Windsor Planning and Zoning Commission to provide recommendations for strategies to include in the Plan of Conservation and Development of the Town’s infrastructure. This meeting will be held this evening at 7:30 p.m. in the Council Chambers.
Mr. Fred Shaw distributed an outline which will be provided to P&Z (See Exhibit E). He also explained that the Town’s sewer service area map shows the areas of development and conservation, which differs from the Town’s map of conservation and development. However, the sewer service area map is consistent with the State’s OPM Plan of Conservation Development. The current Clean Water Grants Program requires that the Town sewer service area map be consistent with the State OPM Plan
of Conservation and Development; the Town sewer service map must take into consideration areas that are environmentally sensitive. Mr. Shaw expressed that the goal always been to support development in Town. The plan always has been to be consistent with the Town’s plan for present and future development. The challenge is in requesting changes in OPM Plan of Conservation and Development that reflect local planning goals and objectives.
E. PUBLIC PARTICIPATION (Items not on the agenda)
None
F. BILLS, CHANGE ORDERS, DISBURSEMENTS
None
G. UNFINISHED BUSINESS
Chairman Richard Aries thanked Ms. Nancy Mulroy and Mr. Fran Ferrero for their service as they have submitted their resignation to WPCA. Chairman Aries is looking forward to the new members that are coming on board including Mr. Don Antaya which was in attendance this evening.
H. MOTION TO GO INTO EXECUTIVE SESSION TO DISCUSS PENDING CLAIMS
None
I. ADJOURNMENT
Motion to adjourn the meeting at 8:05 p.m.
Motion was made by Mr. Ed Havens, Jr.
The motion was seconded by Ms. Carol Fletterick
The motion carried unanimously
Respectfully Submitted,
______________________________
Ether A. Diaz
Recording Secretary
Originally Posted: February 16, 2012
Date Approved: March 6, 2012
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