Alta Way Extension Project Initial Study

Community Development Agency



The roadway will be contained within the public right of way of Alta Way, Mill Valley.

Assessor’s Parcels

The ten lots that will potentially be developed in the future are:
049-041-48, 049-041-43, 049-041-42, 049-041-44, 049-041-38, one legal lot with three APNs (049-042-01, 049-044-07, and 049-044-08), 049-044-30, 049-044-29, 049-044-31, and 049-044-14

Project Engineer

Jason Wong

Project Description

The applicant requests a grading permit approval to extend the roadway at the end of Alta Way for an approximate length of 512 feet. The proposed roadway extension would be located in the right of way and would involve construction of retaining walls to a maximum height of approximately 6 feet. The width of the paved roadway will be 20-foot ending in a fire truck turnaround. Utilities will also be extended to allow future development of up to ten single family residential homes.

Project Status

The County has completed review of the Alta Way Extension Project Initial Study, prepared by the County’s environmental consultant, dated April 2018. The Project involves a Grading Permit proposing to extend Alta Way to provide access to ten (10) residential lots. As required by the California Environmental Quality Act (CEQA), the Initial Study was prepared to provide the County with information to use as a basis for determining if an environmental impact report (EIR) is required. The Initial Study was informed in part by public comments received through a public scoping meeting held in the Tam Valley community on October 12, 2017. Based on the Initial Study, the County has determined that the Project may have significant effects on the environment and that an EIR is required (State CEQA Guidelines Section 15063(b)(1)). Environmental issues of primary concern for the EIR relate to hydrology/water quality/drainage and soil stability, and transportation/traffic.

One aspect of note is that the Southern Marin Fire Protection District has identified inadequate emergency access from the Project site, which poses a hazard for emergency responders and for residents. This would be a significant impact, and a means of secondary emergency egress should be further examined in an EIR. The precise alignment of the emergency access road will be developed through the Draft EIR with input from the Southern Marin Fire Protection District.

The Initial Study will be used to refine and focus the EIR and will be included as an appendix to the Draft EIR, so the information contained in the Initial Study is available for reference and public comment as part of the Draft EIR. Public comments on the Draft EIR will be responded to through the preparation of a Final EIR. The Final EIR will be completed and certified prior to the County’s decision on the Grading Permit request.

During the EIR process, there will be a number of opportunities for public participation, and adequate notice will be provided each time. The first opportunity for public input will be a 30-day scoping period when the County releases the Notice of Preparation (NOP) of EIR for the Project. The purpose of this scoping period is to provide individuals, organizations and agencies an opportunity to raise concerns about the environmental effects of the proposed Project. This will be the second public scoping opportunity for the Project (as noted above, a public scoping session was conducted in October 2017, prior to initiation of the Initial Study). A date for release of the NOP has not been set at this time, but the Project status on the Project’s webpage will be updated when information is available, and subscribers will be notified when the NOP is released. Once the Draft EIR is completed, it will be circulated for a 45-day review and comment period, including a public hearing on the adequacy of the Draft EIR before the Marin County Planning Commission.


Frequently Asked Questions

Audio recording of the Scoping Session

Alta Way Scoping Notice

Environmental Review Documents

Alta Way Initial Study