Trigon provided planning, engineering, and design services to Plaquemines Parish Government for improvements to the sewer system in the Happy Jack area of the Parish.
This area consists primarily of 96 existing camps/houses in a marsh/wetlands area on the unprotected side of a flood protection levee. Sewage from the camps is collected by gravity sewers to six grinder stations, pumped through a 4” to 6” force main for approximately 1.5 miles, and then re-pumped by a larger submersible station.
The physical condition of the sewer system serving the 96 camps is in poor condition, and pipes and the grinder stations have settled/sunk over time. This, coupled with the fact that the area is subject to periodic flooding from tidal action and general high groundwater, results in a significant amount of infiltration and inflow (I/I) entering the sewer system.
Additionally, development of 59 new camps in the area has been approved by the Parish and has begun. This new development will cause additional stress on the sewerage system.
In concert with the Parish and the Parish’s private operations contractor, Trigon performed a preliminary evaluation of the sewer system and evaluated multiple options for improving sewer service in the area. Recommendations include improvements to the gravity system in the area, new pump stations and a new force main, based on both physical condition and capacity limitations of the existing system.
Trigon was also requested by the Parish to develop an implementation plan for the improvements and an overall cost estimate. A total of five phases were defined, which would allow the improvements to be completed as funding becomes available. The phases in the implementation plan were structured to keep the construction of improvements organized in an orderly and systematic approach yet allow several of them to be interchangeable and/or combined to accommodate funding availability, thereby giving the Parish flexibility to implement the construction.
