Work should begin this week, and as early as today, according to Greg Clark, wastewater rehabilitation manager for CU. For the past 2 1/2 years, Clark has overseen the complex project.
An acronym for Strategic Commitment to Protect the Environment, SCOPE 10 is a vast sewer rehabilitation program projected to cost some $30 million over a 10-year period. Arguably, the project could go longer if it evolves into a standard maintenance strategy at the end of the next decade.
Technically, this week’s resumption of the sewer rehab is the second phase; however, it is the first to use money from a low-interest $10 million loan from the State Revolving Fund.
Coordinated by the Tennessee Department of Environment and Conservation, in partnership with the U.S. Environmental Protection Agency, the SRF is a revolving fund in which loans are provided to utility companies statewide for water and wastewater projects. Loans come with a low interest rate and often include a portion that is forgiven.
In CU’s case, the $10 million package includes $451,000 that won’t have to be paid back, and the rest is financed at 1 percent. As CU repays the principal, the funds are returned to the SRF and are disbursed later to utility companies for other water and wastewater projects across the state.
CU funded Phase I of SCOPE 10 through its own resources such as municipal bonds repaid by customers’ wastewater rates. The project covered territory mostly on the city’s southern end, including some of the utility’s oldest sewer lines.
This week’s resumption of the rehab project — similar to the process used in Phase 1 — is the next step that follows an extensive preliminary testing of sewer lines using smoke and closed circuit TV (CCTV) techniques.
This SSES (Sewer System Evaluation Survey), conducted earlier this year, pinpointed wastewater pipes within targeted areas of CU’s service territory that are cracked, broken or have other defects that are allowing inflow and infiltration (I/I) into the lines.
I/I refers to unwanted, extraneous groundwater that seeps into sewer lines and thereby reduces capacity for the flow of treatable effluent. It also contributes to manhole overflows that — when they occur too frequently — can become violations of CU’s NPDES (National Pollutant Discharge Elimination System) permit with EPA.
“We’re doing this to try to eliminate the I/I,” Clark said. “That in itself should help to alleviate overflows.”
He added, “The other big thing about doing this work is it allows us to regain capacity in those sewer lines. This will hopefully keep us from having to do any [additional] projects to upsize those lines due to capacity issues. This saves money in the long run.”
In February, the Cleveland Board of Public Utilities awarded the contract for this leg of SCOPE 10 to American Infrastructure Technologies Corp., a firm from Hanceville, Ala., which is just north of Birmingham. The AITC bid was for $4,817,000, an amount that came in well below CU’s budget projection of $6,015,000.
Unlike Phase I of the sewer rehab work that focused on the city’s southern end, this opening leg of the SRF project will include a much broader area. Its approximate dimensions will be bordered to the north by Mouse Creek Road, to the south by Blue Springs Road, to the west by Interstate 75 and to the east by Keith Street.
“All the homeowners or business owners will be notified in person [about the repair work] if they are at home,” Clark said. “Or, we will attach a flier to their doors.”
The CU project manager said notification should come at least 48 hours prior to the start of work. Whether through fliers or face-to-face, construction crews will assure neighborhood residents or businesses that any sewer service disruption will be for less than one workday.
The AITC flier explains the temporary impact of the sewer rehab work.
“Great care will be taken to protect your property from any impact; however, we ask that you limit your water usage for the day to prevent any backups of water into your home,” the advisory reads. “Please do not do laundry or wash dishes during the time we are lining your sewer main, as your sewer connection will be temporarily blocked.”
The flier adds, “Your sewer connection will be reinstated by late afternoon and you will be able to use your drains without interruption. If you have any questions or issues concerning our work, feel free to ask any of our employees to send a supervisor to speak with you.”
Questions may also be directed to Ramon Hanson, AITC project supervisor, at 205-470-0668; or, to Clark at his direct CU extension at 478-9377.
“People can call me directly,” Clark assured. “I’ll be glad to answer their questions.”
To repair most broken or damaged sewer lines, CU is using a high-tech method called CIPP (Cured-in-Place Pipe). It is a process in which an interior lining is inserted into existing sewer lines from manhole to manhole. This resin-based lining is then “cured” into place by steam or hot water.
The process, which essentially creates a new pipe within the old pipe, is just as effective in restoring sewer lines to maximum flow and greatly reduces the cost. Traditional open-cut excavation is much more expensive, labor intensive and more disruptive to property and business owners, and also creates greater traffic disruption on area roadways.
The CIPP process was used in the opening phase of SCOPE 10 and Clark said close monitoring so far has supported its effectiveness.
In certain isolated cases, damage to sewer lines might be too severe for correction by CIPP, Clark explained. In these instances, excavation is necessary.
“We appreciate everybody’s cooperation and for working with us,” Clark said. “There will be some traffic disruption concerns [especially on Georgetown Road].”
He added, “Certainly, if anyone has problems or questions, we want them to call us and we’ll try to rectify those problems.”
Clark explained the benefits the SCOPE 10 rehab project is bringing to CU customers, to the utility itself and to the city of Cleveland. Some include:
1. “One of the biggest things is it keeps us in compliance with all of our state mandates so hopefully they (regulatory agencies like TDEC and EPA) won’t come in and require additional work,” he said.
2. “Doing this work should allow us to regain some capacity [in the sewer lines],” Clark noted. In any aging sewer system, I/I eventually becomes a problem. Cities across Tennessee have been cited by TDEC and EPA — a few include Nashville, Knoxville and Chattanooga — since 2005 for violations that can be corrected only through one means; that is, extensive sewer rehabilitation strategies similar to Cleveland’s SCOPE 10.
3. “[By eliminating I/I] we won’t be treating extraneous water at the [wastewater] treatment plant,” Clark stressed. “Regardless of the source of the water, whether it’s I/I or from our customers, it’s all going to be treated at the plant. So, in the case of I/I, it’s a case of treating simple groundwater which comes into the plant from the sewer lines.” Treating groundwater is not only unnecessary, it adds to the treatment plant’s operating expense.
4. And speaking of I/I’s impact on CU’s wastewater treatment plant, it forces equipment to operate longer, which burns more electricity, increases wear and tear on equipment and in the long run increases total costs to the utility, Clark stressed.
SCOPE 10 is as much about being proactive as it is about making badly needed physical repairs, the sewer rehab manager stressed. Because CU has already launched SCOPE 10 and has a firm strategy in place for modernizing its sewer system, agencies like TDEC and EPA aren’t expected to get involved.
This has not been the case with other cities — many of them much larger than Cleveland — that have been mandated by EPA to begin sewer rehab initiatives of their own and to pay for them through major sewer rate hikes.
While CU has been able to limit its wastewater rate increases to about 5 percent, utility customers in other areas haven’t been so fortunate. Reportedly, hikes across the state in other jurisdictions have ranged from 50 to 300 percent.
In Hamilton County, for example, a sewer rate hike of 39 percent was recently imposed, Clark said.
In Knoxville, $900 million has been spent so far on sewer rehab; more is expected, he pointed out. In Nashville, the tab is projected to hit $1.5 billion; and in Chattanooga, costs are estimated at $200 million to $300 million, but these are tentative amounts, Clark explained.
Once this phase of SCOPE 10 is completed, CU will have restored another 49,300 feet of its sewer main. That’s about 9.3 miles worth.
That’s the good news. The bad news is the local utility operates about 360 miles of sewer line.
But Clark urges CU customers not to be alarmed. Much of the existing pipe is still in good operating order, as shown by previous SSES tests. That’s the whole purpose of smoke testing and CCTV techniques — to help CU and its contractors “prioritize” the areas of the system that need immediate work.
“... The work we’re doing now is just a tiny portion of what we have [in the whole sewer system],” Clark said. “So obviously, you want to spend your money the best you can because it’s a limited amount. So, you try to assess the areas and decide where, and how, you can get the biggest bang for your buck.”
Of past SSES testing, he pointed out, “Some of the areas we have looked at are fine ... where we can say, ‘At this point we don’t need to take any action, but in a period of 20 years from now it may be that due to age it might need some work.’”
Clark compared it to an asset management program where CU is taking full inventory of its property, equipment and total system, and determining their current physical condition and life expectancy.
“It’s a planning thing for us,” he noted. Such planning helps CU look ahead to determine budget projections for the future.
As has been a practice at CU for years, the local utility does not design budgets one year at a time. Instead, the utility looks ahead 10 years. It’s a practice that is necessary for some utilities, especially those serving communities with a rapid growth rate. Cleveland is a prime example.
The new phase of SCOPE 10 won’t only rehab almost 10 miles of sewer line, Clark reported to the utility board in February. It will also upgrade 2,270 vertical feet within 280 manholes; and, it will include the rehab or replacement of 518 sewer laterals, which is the stretch of pipe running from the sewer mains to customer properties.
Work will also include the replacement of vented manhole covers with solid covers in areas that receive “sheet flow” during heavy rainfall. It will also provide for the insertion of “inflow dishes” in manholes located in areas susceptible to sheet flow or ponding water during heavy rainfall.
“[Each day during the project] we’ll try to talk to the folks [in the neighborhoods],” Clark assured. “Typically, it will affect from 10 to 20 homes in between the manholes. If there’s an apartment complex or something, obviously that will affect more.”
Work is expected to begin early each morning and will be wrapped up by late afternoon, Clark noted.