Water and Wastewater Pipelines
Lockwood, Andrews & Newnam, Inc. (LAN) was selected as one of the design teams for the City’s 2015 water and wastewater pipeline maintenance and rehabilitation efforts. This is an ongoing program where water transmission and distribution as well as wastewater collection lines are evaluated and assessed prior to development of rehabilitation or replacement design and construction. LAN was assigned the assessment and design for 34 separate utility segments throughout the City of Dallas.
Elements of the various segments in this assignment required open cut replacement as well as evaluation and development of design for various trenchless rehabilitation technologies. In total, design included improvements to more than 50,000 LF of 8- to 12-inch water and wastewater pipelines. Challenges overcome included working within the highly congested Dallas Central Business District where segments are in close proximity to buildings and large underground utilities. One notable segment included an existing alignment running directly beneath the Dallas World Aquarium. Other segments required coordination with TxDOT, Dallas Area Rapid Transit (DART), and various franchise utilities. In maximizing value to the City and constituents, each segment was evaluated separately to determine the most appropriate rehabilitation/replacement solution, with open cut construction, cured-in-place-pipe, pipe bursting, microtunneling, and traditional boring all being utilized in various areas. For the notable Dallas World Aquarium crossing, a newer technique known as pipe eating was specified.
The project included assessment, preliminary, and final design with each segment packaged for construction by the City of Dallas.
At a glance
Preliminary and final design includes more than 50,000 LF of water and wastewater pipelines in the Dallas system
Rehabilitation and replacement includes the use of multiple trenchless technologies, including pipe bursting, microtunneling, and cured-in-place-pipe
By developing an accelerated design schedule, the design phase was shortened by two months from the originally budgeted 12 months
Design segments required interaction with TxDOT, Atmos Energy, and Dallas Area Rapid Transit to coordinate proposed crossings
Segments included in the design for this effort included environmentally sensitive areas and heavily congested urban/business districts
Included in the design phase of this project was a pilot program for large meter assessment and sizing in the City's transmission system
These design efforts are components of the City of Dallas's annual water and wastewater maintenance and rehabilitation program.
Assessment and rehabilitation efforts by the City are focused on decreasing losses in the water transmission and distribution system.
A primary objective for wastewater utility rehabilitation is the reduction of Sanitary Sewer Overflows (SSOs) throughout the City.
Pipeline Design, Assessment & Rehab