Trinity River Vision Project – Part 7: Gateway Park Site E Sanitary Sewer Relocation
Project Details
Open Shield Pipe Jacking
- 48″ steel casing for 16″ gravity sewer
- 325′ drive beneath Interstate 30
HDD
- HDPE siphons (12″ and 18″)
- Two 740′ bores beneath Trinity River
Geotechnical Conditions
- Lean clay and clayey sand
- Limestone bedrock
Challenges
- Flat grade (0.20%) for IH-30 crossing
- Mixed face soil conditions
Project Overview
As a trenchless subconsultant to Kimley-Horn, Bennett Trenchless Engineers provided design assistance for two trenchless crossings for utility relocations associated with the Trinity River Vision Project. The Part 7 – Gateway Site E Project involved the relocation and replacement of 2,200 feet of existing sanitary sewer, including major crossings of the existing Trinity River and Interstate Highway 30 (IH-30). The project used a mixed-bag of trenchless construction methods including HDD, open-shield pipejacking, and auger boring. BTE selected HDD for construction of the twin, inverted siphon crossings of the Trinity River, and open-shield pipejacking for the gravity sewer crossing of IH-30. Challenges on the project were varied and included mixed conditions of soils overlying limestone bedrock; work area and site access constraints; and coordination with USACE regarding environmental risk mitigation for hydrofracture.
Project Details
Open Shield Pipe Jacking
- 48″ steel casing for 16″ gravity sewer
- 325′ drive beneath Interstate 30
HDD
- HDPE siphons (12″ and 18″)
- Two 740′ bores beneath Trinity River
Geotechnical Conditions
- Lean clay and clayey sand
- Limestone bedrock
Challenges
- Flat grade (0.20%) for IH-30 crossing
- Mixed face soil conditions
Project Overview
As a trenchless subconsultant to Kimley-Horn, Bennett Trenchless Engineers provided design assistance for two trenchless crossings for utility relocations associated with the Trinity River Vision Project. The Part 7 – Gateway Site E Project involved the relocation and replacement of 2,200 feet of existing sanitary sewer, including major crossings of the existing Trinity River and Interstate Highway 30 (IH-30). The project used a mixed-bag of trenchless construction methods including HDD, open-shield pipejacking, and auger boring. BTE selected HDD for construction of the twin, inverted siphon crossings of the Trinity River, and open-shield pipejacking for the gravity sewer crossing of IH-30. Challenges on the project were varied and included mixed conditions of soils overlying limestone bedrock; work area and site access constraints; and coordination with USACE regarding environmental risk mitigation for hydrofracture.