Hanover Township Sanitary Sewer Interceptor

Hanover Township’s Solomon Creek Interceptor was constructed in the early 20th century and consists of approximately 18,600 feet of 24- through 39-inch vitrified clay tile pipe.  The interceptor follows and crosses Solomon Creek for a majority of it length, requiring the use of two inverted siphons.  Investigations determined that portions of the interceptor has little to no slope with some sections actually having negative slopes.  These conditions coupled with age of pipe (original installation circa 1916) has resulted in significant accumulation of debris, including grease, grit, manhole bricks, and clay tiles.

Project: Hanover Township Sanitary Sewer Interceptor

Location: Hanover Township, Luzerne County, PA
Owner/ Client: Hanover Township

Project Status: On going

Challenges V. Solutions

Challenge Borton-Lawson was brought on in early 2016 after a numerous sewage backups took place along the interceptor following moderate precipitation events. Emergency actions were implemented to temporary resolve the backups, but it was clear that a longer term, sustainable solution was required. Complete replacement of the existing system would take care of all problems, but this option was not feasible due to cost.

Solution Several grants were obtained to begin investigative work to determine the condition and capacity of the existing Solomon Creek Interceptor with the goal of prioritizing improvements. Borton-Lawson utilized SewerGEMS to hydraulically model the downstream section of the interceptor, which was previously designed to be replaced. The hydraulic analysis and subsequent CCTV inspection revealed that that this portion of the system could be lined via cured-place-methods, allowing approximately twice as much interceptor to be rehabilitated as previously planned. Borton-Lawson continues to evaluate the system to prioritize improvements