Storm Drainage System Replacement & Rehabilitation Project

  • Project typeSystem Rehabilitation

Project Description 

Over the past several years, Public Works Operations Maintenance group identified and compiled an ongoing list of storm drain pipes and structures that are in critical condition and are in need of repair or replacement. The pipes are either cracked, rusted, or rotted. This project proposes to maintain the integrity of the storm drain system through replacement or rehabilitation of deteriorated storm drain infrastructure. Thus, eliminating potential pipeline blockages that could cause street flooding. 

Project Status

  • Construction Contracted awarded on September 27, 2021
  • Construction Schedule and additional project information will be provided when it becomes available. 

Scope of Work

  • 1,415 linear feet of broken storm drain pipe to be replaced
  • 416 linear feet of 10-inch pipe to be upsized to 12-inch pipe
  • 2,443 linear feet of pipe to be cured-in-place pipe (CIPP) lined
  • 21 catch basins to be replaced
  • 4 storm drain structures to be replaced

Location

The pipes to be rehabbed are in 13 different locations throughout the City.

Storm Drain pipes replacement location Map

FAQs

  1. Why do pipes need to be rehabilitated?
    Corrugated metal pipes (CMP) have rusted out to the point where there are holes in the pipes. These segments cannot be repaired and need to be fully replaced.  Other pipe segments have cracks due to concrete deterioration over time, tree root intrusion, or construction activities. Pipes segments that are shallow, limited cover, may cave-in from the weight of the heavy construction vehicles constantly driving over them. The project reduces flood risks by making sure that the storm system is properly maintained and functioning.
  2. How are the pipes rehabilitated?
    The condition of the pipe will determine if the pipe will be replaced or cured-in-place pipe (CIPP) lined. Lining provides structural support in the pipes, extends the product life, prevents root intrusions while avoiding the need to trench in the street. If there are no holes or significant cracking, the storm drain pipe can be CIPP lined. Pipes with significant cracking or pipes beyond repair will be replaced. As a result of the pipe replacements, additional work such as replacing storm drain inlets, manholes, striping, sidewalk, curb and gutter, and curb ramps may be required.
  3. Why are some pipes being upsized? 
    There are existing pipes that are 10-inches that will need to be upsized to 12-inch pipe. Part of this project includes upsizing pipes to meet minimum design standards as set by the approved 2015 Storm Drain Master Plan. The design standards require pipes to be a minimum of 12-inch diameter pipe in the public right-of-way. Pipes less than 12-inches have less capacity, are difficult to maintain and can clog.
  4. How is this project funded?
    The Storm Drainage System Replacement and Rehabilitation project is funded by the Storm Water Management Fee ballot measure, approved by Palo Alto voters in April 2017. This project proposes to maintain the integrity of the storm drain system through replacement or rehabilitation of deteriorated storm drain pipes, manholes, and inlets.
  5. Is there Green Stormwater Infrastructure (GSI) included with this project?
    No, there is no GSI on this project. This project comes from funds specifically dedicated to maintaining and repairing the storm drain system. Only pipes that need repair are included in this project. Most of these pipe locations are located in the middle of the street, and do not have a planter adjacent to the catch basin that could be altered and converted to act as a GSI feature.
  6. Has this project been coordinated with other departments?
    This project includes coordination with the Utilities Department, Public Works Engineering Streets Group and Public Works Operations Maintenance Group.