Active Projects

A view looking over the wastewater plant, with pools, railing and machinery, buildings
  1. WWTP Rehabilitation Project (Phase 2) Update
  2. Digester #2 Rehabilitation Project
  3. Miller-Sycamore Manhole Rehabilitation
  4. Miller-Sycamore Sewer Trunk Lines Rehabilitation

Location

450 Sycamore Avenue
Mill Valley, CA 94941

Phase Information & Update

The Waste Water Treatment Plant (WWTP) Rehabilitation Project (Phases 1 and 2) is 98% complete. The first phase of the WWTP Master Plan implementation began in April 2018 and was completed in 2020. Phase 2 started in 2020 and will be completed by the end of 2023 The primary goal in this $20+ million dollar program is to help ensure reliable treatment of wastewater, as well as compliance with regional, State, and Federal regulations. Numerous upgrades of major equipment and rehabilitation of existing infrastructure are key components of these two phases of this SASM construction program.

Completed Project Elements and Ongoing Work Activities

The following is a list of completed project elements and ongoing work activities that are progressing well and remain on schedule to be completed by November 2023:

•    Headwork Building Belt-press Room Ventilation Modifications:100% complete.
•    Rehabilitation of Secondary Clarifier Number 1: 100% Complete
•    Rehabilitation of Secondary Clarifier Number 2: 100% Complete
•    Hypochlorite Storage and Transfer System:100% Complete
•    Rest Area Improvements: 100% Complete
•    Digester Tank Number 1 Floating Cover Replacement: 100% Complete
•    Cathodic Protection System (CP-1) Replacement: 100% Complete
•    Trickling Filter #1 & #2 Media Replacement: 100% Complete
•    Main Plant Switchgear Replacement:100% Complete
•    Digester Tank #2 Floating Cover Replacement: 85% Complete

 

Notice of Construction & Parking Restrictions

450 Miller, 457 Miller, & Sycamore Park

October 2 – October 16

Maggiora & Ghilotti has contracted with the City of Mill Valley to perform sewer system improvements work under the Frontage Road Force Main Improvements Project. Upcoming work as part of this project consists of rehabilitating the sewer main from Miller Ave to and through Sycamore Park.                                                                                     

The rehabilitation work includes lining the existing sewer main with Cured in Place Pipe (CIPP) and rebuilding two (2) manholes on Miller Ave to accommodate the lining work. One manhole is on Miller in front of 450 Miller; the other manhole is at the back of the parking lot for 447 Miller. This project is an important health and safety improvement and will reduce the risk of a sewer spill and potential environmental impact.

The following is the work scheduled:

Mon 10/2 7AM – 5PM

Excavate and Demo Manhole 1A in 447 Miller parking lot.

Four Parking Spaces at the back of the parking lot will be closed to complete this work.

Tues 10/3 thru Thurs 10/5 7AM – 5PM

Excavate, Demo, and partially Rebuild Manhole 1 in front of 450 Miller.

The right lane in the eastbound direction on Miller Ave will be closed to complete this work.

Mon 10/9 7AM – 6PM (SYCAMORE PARK WILL BE CLOSED)

CIPP Line existing Sewer Main from 447 parking lot through Sycamore Park.

Also, parking nine spaces at the back of the 447 Miller parking lot will be closed to complete this work.

Wed 10/11 (NIGHT WORK) 8PM - 6AM

CIPP Line existing Sewer Main from 450 Miller to 447 Miller parking lot

The right lane in the eastbound direction on Miller Ave, curbside parallel on-street parking, bike lane and the back of 447 parking lot will be closed to complete this work.

Thur 10/12 thru Fri 10/13 7AM – 5PM

Complete the rebuild and backfill of Manhole 1 in front of 450 Miller.

The right lane in the eastbound direction on Miller Ave will be closed to complete this work.

Mon 10/16 7AM – 5PM

Complete the rebuild and backfill of Manhole 1A in 447 Miller parking lot.

Parking Spaces at the back of the parking lot will be closed to complete this work. About Cured in Place Pipe: CIPP is a common and cost-effective method to rehabilitate the existing sewer main with little to no excavation or street removal. This method provides a seamless lining of the existing main. During the rehabilitation pipe lining process, you may smell a chemical-like odor coming from your private drains. You may mitigate odors by pouring 1 gallon of water down all floor drains or any rarely used sinks/tubs/toilets to ensure that a water barrier is maintained in the traps.

Restricted Parking: Some spaces on the south shoulder of Miller Ave during the lane closure on Miller; and several 447 Miller Ave parking lot spaces during work in the parking lot as indicated in above schedule.

We apologize for any inconvenience caused by these construction activities, and we will be working as quickly as possible.

Project Updates are available at: www.cityofmillvalley.org/2023/2023-Sewer-Rehabilitation MVConnect is the City of Mill Valley eNewsletter sent twice a month directly to your inbox with project updates. You can subscribe at www.cityofmillvalley.org/675/MVConnect

If you have any questions or issues our field personal cannot resolve, please contact:

Maggiora & Ghilotti at 415-459-8640

or

City of Mill Valley Construction Manager, David Stier at 415-717-3496