Case Study from Trenchless Rehabilitation Evaluation of North McKinney Interceptor Main for North Texas Municipal Water District

This paper presents a case study of a pipeline rehabilitation project for North Texas Municipal Water District (NTMWD). The North McKinney Interceptor main was constructed in 1992 to convey flow from the City of McKinney to the McKinney Lift Station adjacent to the Regional Wastewater Treatment Plant (RWWTP). The overall main is approximately 44,200 ft long of reinforced concrete pipe and rubber gasketed ASTM C-76 pipe. The second phase of project consisted of evaluating trenchless pipe and manhole rehabilitation to improve 22,540 liner feet of existing 36-, 30-, 27-, and 24-in. diameter sanitary sewer line, referred to as the North McKinney Interceptor Improvements, Phase 2. The subjected pipelines were inspected by CCTV method and condition assessment performed based on ASTM F1216. According to ASTM F1216, the pipelines are classified as "partially deteriorated condition." After assessing the condition of pipes, four rehabilitation alternatives proposed. These alternatives included (1) Conventional Method (Opencut), (2) Cured-in-place pipe, (3) Sliplining, and (4) Spray-applied pipe lining. The objective of this study is to investigate advantage and disadvantage of each proposed alternative and perform cost analysis to find the most reliable and cost-effective method.