# Los Angeles County Sanitation Districts Questcdn #10354741

Retaining-wall ground improvement and rehabilitation of two plant outfalls

**Posted:** September 29, 2026
**Respond By:** November 17, 2026
**Identifier:** 10354741
**NAICS:** 237990, 237110, 238110

Los Angeles County Sanitation Districts is seeking construction services to stabilize a retaining wall and rehabilitate two outfalls at the Valencia Water Reclamation Plant.
- **Government buyer:** Los Angeles County Sanitation Districts; no sub-agency or contracting-office details are provided.
- **Project scope:**
  - Improve the middle 1,200-foot section of the existing retaining wall using Cement Deep Soil Mixing (CDSM) walls and secant pile walls with ground anchors along the riverbank.
  - Rehabilitate two plant outfalls by demolishing and replacing concrete pipe, slip-lining an existing concrete pipe with FRP pipe, replacing a headwall, and installing riprap.
- **OEMs and vendors:** No product manufacturers or construction vendors are named. QuestCDN is identified as the platform for bid materials and questions.
- **Notable requirements:** Prime contractors must attend a mandatory jobsite walkthrough. The latest notice does not state a construction duration or bid deadline.
- **Period of performance:** An earlier notice states 556 working days after the Notice to Proceed; the Notice to Proceed date is unspecified, and the latest notice does not restate the duration.

### Description

The project covers ground improvement along the existing 1,200-foot middle section of the retaining wall. Work includes constructing Cement Deep Soil Mixing walls and secant pile walls with ground anchors along the riverbank. It also includes rehabilitating two plant outfalls by replacing and slip-lining pipes, replacing a headwall, and installing riprap near the southern end of the wall. Prime contractors intending to bid must attend the mandatory jobsite walk-through on October 15, 2026.

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