Sanitary Sewer Armoring - Holmes Run Project
Project Summary
Current Phase: Planning
Sponsor Project Manager: Arbina Shrestha, P.E. Transportation and Environmental Services
Managing Project Manager: Tafesse Gyse, P.E. Department of Project Implementation
Project Description
The City completed a project to inspect all sanitary sewers in stream areas to assess their risk of failure due to stream erosion. Under that study, two sanitary sewers crossing Holmes Run just upstream of I-395, were determined to be at risk of failure. The casing of the upstream sewer is cracked and broken exposing the pipe, and the downstream segment has been undermined by the erosive forces of the stream.
This project provides armoring to those two sewer segments in Holmes Run to preserve the integrity and extend the useful life of the sewer system and protect the environment. The project consists of three phases with the planning phase to be completed by fall of 2024. The design and construction phases are anticipated to begin late 2024 and early 2026, respectively
Project Funding
Total Budget: $1,573,300
Planning: $273,300
Design: $250,000
Construction: $1,050,000
FUNDING BREAKDOWN
This project is funded using Sanitary Sewer Enterprise Fund revenues and is programmed in the City's Capital Improvement Program
Schedule
Planning: Summer 2024- Fall 2024
Design: Fall 2024- Winter 2026
Construction: Winter 2026- Winter 2027
Planning Phase
Planning Overview
- Field Inspection/Condition Assessment – Inspected total of 157 sanitary sewer segments in stream areas using CCTV camera per NASSCO (National Association of Sewer Service Companies) guidelines to document internal structural and operation and maintenance (O&M) conditions and visually inspected sanitary sewers to assess the risk of failure due to stream erosion or external structural defects.
- Rehabilitation Recommendation – Reviewed inspection reports and photos to determine consequence and likelihood of failures and ultimately assessed the risk of failure of those sanitary sewers. A total of seven sewer segments were determined to be at a risk of failure and were proposed for armoring. Out of which, two segments will be armored under this project.
- Cost Estimate – a planning level cost estimate was performed for design and construction services.
Planning Public Outreach
No public outreach was conducted at the planning stage of this project. As part of the design and construction of this project, the City will perform stakeholder engagement with the community to discuss the need for the project and how to best protect the existing sewers while minimizing impacts during construction.
An outreach plan will be developed prior to detailed design starting.
Contact
Arbina Shrestha
Civil Engineer III
City of Alexandria, Virginia
T&ES/Sanitary Infrastructure Division
(703) 746-4243 or 4014