Blueprint Columbus Addresses Lateral Rehab on the Private Side

Can private side service lateral rehabilitation really make a difference in the battle with inflow and infiltration (I/I)? The City of Columbus, Ohio, thinks it can.

So much so that the City Council deemed I/I a “nuisance” to public and environmental health when, during heavy rain events, raw sewage is discharged into local rivers, streams and tributaries. This sparked the creation of a citywide ordinance granting the public utilities director authority over the private side so that the entire service lateral can either be rehabilitated or replaced at the City’s expense.

It’s a familiar story we have all heard in the industry, municipalities under EPA consent decrees for sanitary sewer overflows (SSOs) and combined sewer overflows (CSOs) to require the rehabilitation of their existing underground infrastructure in order to protect the public and environment from raw sewage spills.

The City of Columbus is no exception: two consent decrees were issued in 2002 and 2004 for SSOs and CSOs that were the impetus for the City to develop a Wet Weather Management Plan in 2005. This plan included plant upgrades, construction of relief pipes/tunnels, pipe upsizing, mainline cured-in-place pipe (CIPP) lining, and manhole rehabilitation, all of which reduced the I/I in the system, but not enough to mitigate the SSOs.

So, the City chose to look at the situation from a different perspective and come up with a comprehensive, holistic approach to their rehabilitation efforts. Mainline CIPP and manhole rehabilitation had already been performed. So, instead of treating the symptoms of overflows with expensive, rarely used tunnels and other infrastructure that cost billions, the city invested that money in solving the actual problem of I/I occurring on private property.

Thus, Blueprint Columbus was established in 2012 and still successfully continues to this day, more than a decade later. The Blueprint Program consists of four pillars, the cost of which are completely paid for by the City:

• CIPP rehabilitation of private laterals up to within 5 ft of the structure foundation.
• Downspout redirection to storm drains.
• Option for basement sump pump installation in special cases.
• Create Green Infrastructure areas throughout the City to assist with capturing and filtering excessive rain water.

All the above components are important aspects of the program, however for the purpose of this article, we will focus on the private side lateral CIPP rehabilitation. The City identified 20, 1,000-acre, project areas consisting of 3,000 to 4,000 residences, which are then further divided into smaller phases and solicited for the procurement process.

Specifications for the rehabilitation require the contractor to install lateral CIPP with a full-wrap connection inside the main, sealing the lateral/main interface, and extending to within 5 ft of the foundation of the house or structure. The average lengths of these laterals measure anywhere from 60 to 90 ft.

BLD Services LLC has been the awarded contractor for seven out of eight Blueprint projects that have been solicited thus far and has renewed approximately 5,000 laterals to date. BLDs unique lateral installation process does not require the need for a clean-out or secondary access point on private property, so the entire lateral liner and full-wrap at the interface is completed in just one installation.

This may sound commonplace, but in the CIPP lateral rehabilitation market, these are very long runs that are being installed from mainlines that measure 8 to 24 in. in diameter without the need for a secondary access point on private property. Not only does this safeguard the contractor from having to coordinate with every homeowner for property access, but it also saves the City the high cost of cleanout installation since all work can be performed from manholes located in the city-owned easement or right of way.

Funding for the work on the private side of the lateral is not at the homeowner’s expense, but rather coming from SRF funds. An innovative approach that is rarely practiced in other municipalities but has proven to be essential in removing enough I/I from the system to satisfy both consent decrees.

After mainline and manhole rehab, initial flow data results showed a 25 to 35 percent decrease in I/I. However, the results jumped to anywhere between 30 to 40 percent in additional I/I reduction after completing lateral rehabilitation on the private side, equaling 65 to 75 percent of I/I mitigation after comprehensive rehab of the system.

The City is seeing a worthwhile return on investment with this program, and subsequently plans to rehabilitate 90 percent of private sewer service laterals in the 20 identified Blueprint areas by 2045.

According to city project manager Nick Domenick, P.E., city officials realized that through this program they can rebuild neighborhoods, increase property values, utilize local labor to perform the work and transform the City, but they also knew they would need to engage the residents for approval to perform work on private property.

Hence, the City Council authorized a local ordinance for authority over the service lateral from the mainline to the building or structure for the duration of the rehabilitation, and then the ownership and maintenance of the lateral, and the other aspects of the program, is turned back over to the homeowner. Initially, there was concern from the residents, however the City’s public information officer led a huge outreach campaign to educate the citizens on the overall benefits of the program, resulting in public acceptance and even appreciation for the investment in their neighborhoods.

Since its inception, Blueprint Columbus has gained significant citizen support, especially in older, underdeveloped areas. The City is investing in the local community, having a positive impact on the residents and restoring the environment in the process, leaving things better than they found it.

Nicole Little is the marketing manager at BLD Services.