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Friends of West Tam Valley

Public Comments On Notice of Public Scoping Session, Alta Way Extension Project Initial Study

Posted by: Lee Budish - October 12, 2017 - 2:46 PM PDT

Friends of West Tam Valley (FWTV) submittted the following Public Comments On Notice of Public Scoping Session, Alta Way Extension Project Initial Study, October 12, 2017.

The following public comment letter has been sent to the the Marin County Development Agency and the following Marin County staff and officials: Rachel Reid, Environmental Coordinator, Jason Wong, Assistant Engineer, Curtis Havel, Senior Planner, Dan Sicular, Consultant, Raul Rojas, Director of Public Works, Brian Crawford, Director Community Development Agency, and Kathrin Sears, Supervisor, District 3.

At the July 10, 2017, Public Hearing on a County initiated merger of 3 parcels on upper Alta Way, Marin County Planning Commission board member, Margot Biehle, called the proposed site slated for development a “disaster zone” and acknowledged that this is an area with “significant environmental concerns.”

She is correct. All of us who live in the area are extremely concerned about the environmental impact to the lives, homes and the Tam Valley Community if and when upper Alta Way is developed. There is great cause for concern since the site of the proposed large-scale development is on a ridge above a steep and unstable hillside that has a history of landslides. This area is also land-locked as a result of 100 years of development of the surrounding area known as Tam Valley, so emergency access will be extremely limited.

In the late 1990’s, Pacific Union also had faced significant issues and concerns related to the build-out of upper Alta Way. Marin County at that time had foresight and believed it was imperative to safeguard the area’s residents. They negotiated with Pacific Union to designate three lots on upper Alta Way as “Open Space Easements.” David Zaltsman, Deputy County Counsel in a letter to the Marin Board of Supervisors dated April 29, 2003, acknowledged that:

…Assisting in keeping the parcels as some sort of private open space is clearly in the public interest as the development in this area is overly dense based upon modern zoning standards for the area and the sites are physically constrained.

Tam Design Review Board (TDRB) also reviewed the related Brown Design Review application for one house and grading extension of Alta Way at their April 6, 2016, public hearing and voiced their concerns in a letter dated April 21, 2016, to Brian Crawford.

TDRB is concerned that this Design Review request is a Trojan horse for a future sub-division along the present paper streets. TDRB recommends that county planning request a Master Sub-Division Plan, with all the required planning requirements - EIR, Stream ordinance review, Road size &grading impacts, Fire hydrants, Tree removal impacts, Utility improvements –elec., water- gas – storm water, sewer, home site grading impacts, Road plan showing the paper streets connecting to existing surrounding roads and the traffic impact, etc. A piece-meal development approach will have cumulative impacts streets bounded by this development will be impacted for years. TDRB questions if major development of this size is appropriate for the area?

It is our understanding that the Marin County Community Development Agency is using an antiquated 1919 subdivision map for the basis of development without mandating that the developer provide a new map up to current subdivision regulatory standards. Almost 100 years have gone by since this map was created and time and nature have altered the topography of the land.

Considering these long standing concerns, does the Department of Public Works and the Community Development Agency have any recent studies or data that adequately assess the environmental and public safety impacts of building the proposed development?

It is difficult to comment at a Public Scoping Session when there is so little information or analysis included in the Initial Study Notice. We see no evidence that the County or the applicant have adequately addressed potentially significant impacts on water and air quality, species and habitat protection, or public safety issues in the event of fire, emergency evacuation and landslides. Nevertheless, based on our day-to-day living experience living adjacent to the proposed development we are extremely concerned with these and other impacts, potential dangers and hazards.

The Friends of West Tam Valley are concerned that the safeguards, protective measures and accommodations required to protect the watershed and animals, mitigate against erosion and landslides, in order to safeguard residents and their homes from significant environmental impacts are inadequate.

1. The Application for the Alta Way Road Extension Project is Incomplete

In a letter dated March 6, 2017, to the Marin County Board of Supervisors (BOS), The Friends of West Tam Valley (FWTV) respectfully requested the removal of consideration of the Alta Way Extension Project, Initial Study, from the agenda of the BOS meeting on Tuesday, March 7, 2017.

The proposed grading application was obviously only a first step to enable a larger-scale development in the future, but without providing any information about that development, which would allow the County and residents to adequately assess its impacts.

The June 1, 2016, Alta Way grading application has now morphed into an Initial Study with a minimum of 10 residential lots to be developed on Alta Way and Fairview Avenue. This avoids analysis of the developer’s intention to request an extension of Fairview Avenue towards Shoreline Highway to service additional vacant lots, in the future. A master plan detailing the size and siting of the homes, their design and heights, infrastructure improvements, management of storm waters and run-off and other such concerns, must be provided by the developer in order for the County to conduct a reasonable and proper Public Scoping Session for environmental review. Only then can the true magnitude of this development be addressed.

We agree with TDRB that a Master Plan for a subdivision should be required to be submitted as well as requiring a more comprehensive CEQA process. CEQA contemplates such scenarios and requires that EIRs be prepared where future related development is reasonably foreseeable. The Initial Study Public Scoping Session for the Alta Way grading application is an attempt to circumvent the required CEQA process by “piecemealing,” and is therefore inappropriate for a large-scale development of this kind.

2. Soil, Soil Stability, Soil Erosion and Documented Landslides on Hillside Construction/ USGS

It is our understanding this proposed extension of Alta Way and the initial 10 residential lots is located in a highly vulnerable Soil Stability Zone 3. There have been two documented landslides 300 yards from this development as well as numerously documented landslides in this pocket of Tam Valley. An extensive and comprehensive geological report with multiple samples must be required on the whole of the 4 acres slated for future development—not just on a piecemeal sample.

An engineering report must also be required to assess and evaluate the impacts of the proposed 6’ high retaining walls. Details and information as to how many retaining walls or other information such as engineering, length, thickness, and underground construction of these walls are not provided. The review must include a comprehensive environmental impact on homes below these proposed retaining walls since the slopes are extraordinarily steep; there is concern that the underground deep drilling on a slope above these homes may weaken the already unstable geology of the hillside and result in landslides.

An engineering report must also be required to evaluate and assess if the hillside can accommodate the weight of homes and the development of two paper streets for not only the short-term development of upper Alta Way but include the potential long-term development since the merger of Alta Way Road to Fairview will allow access to additional parcels for development.

The report must include impacts of tree removal and existing vegetation including the native 100-year-old purple needle grass with 20’ roots must be required. Trees provide soil stability and help prevent erosion. Erosion issues should be carefully examined in relation to the removal of trees and native grasses.

There are environmental health concerns regarding the 512’ road extension and retaining walls since the proposed road will is in extremely close proximity to homes along Browning Street, Browning Court, Alta Way, Sunnybrook, Everest and Denise Courts which border Fairview Avenue. The chemicals and sediment from products to build the roads and retaining walls including the run-off, and the resultant sediment, dust and fumes of increased traffic will enter these homes and may cause health issues for children, elderly, asthmatics and those with weak immune systems.

3. Fire Safety and Evacuation Plan

In the event of an emergency, how will residents evacuate the area, since merging onto an already congested and gridlocked Shoreline Highway if their only option?

A comprehensive Southern Marin Fire Department study should be required to determine the potentially significant impacts on emergency response time for ambulances and fire department vehicles, and to include an evacuation plan for all the existing and proposed homes to be serviced by extending Alta Way and Fairview. This steep hillside development is in a high-risk fire area and is also a documented Wildland-Urban Interface.

There are 35 existing homes that currently use the Alta Way entrance. Add that to the additional 10 residential lots identified in the Initial Study notice for development and there will be 45 homes with an estimated 2 vehicles per home requiring exit from Alta Way at Shoreline during an emergency. This does not include the potential for the development of the additional 18 vacant residential lots in the subdivision, once the new roadways are in place. Note that the cul-de-sac road parallel to paper street Fairview Avenue is Chamberlain Court with one-way egress via Shoreline Highway. Chamberlain Court is 33’ wide and services 38 homes.

The proposed 20’ wide extension of the road needs to be re-evaluated and reviewed to assess if it can accommodate the exit plan including emergency vehicles. The paper road is clearly 40’ wide on the parcel map. Why would a 20’ wide road be approved forsaking a wider road for the safety of homes and residents in such a restricted access high-risk fire danger area?

Fire and emergency vehicle access are imperative as well as provisions for an adequate number of fire hydrants with more than adequate water pressure to reach this restricted access high-risk fire area.

4. Drainage, Hydrology, Flood Control, Storm Water Issues, Seasonal Springs and Underground Streams, Riparian, Tributaries of Coyote Creek, Rising Sea Levels

Hydrology reports with drainage calculations are needed to analyze the cumulative impact that the proposed development of the build-out of upper Alta Way will have on the watershed, tributaries, homes and roads in the area as well as analysis an assessment of current, limited and antiquated drains and culverts. Many of these drains and culverts were created in the late 1950’s and early 1960’s. They are eroding and corroding and are barely able to accommodate the current run-off. Storm drain calculations should incorporate the existing storm drain lines to verify capacity and stability of structure. The last documented drainage study of the area is 1984.

As acknowledged on the Marin County.org website addressing the Marin Sea Level Rise Project, “Marin County already experiences more frequent flooding both on the Pacific coast and in West Marin and along our bay shorelines, impacting roadways, drainage and utilities, and disrupting people’s lives. These impacts are expected to increase in frequency and severity as sea level rise accelerates. Marin County is facing the challenge by planning for climate change in collaboration with Marin’s cities and towns.”

Climate change and extreme precipitations has invalidated the notion of a 100-year flood and nowhere is this more evident than at Shoreline/Manzanita and Coyote Creek. Marin County currently has two main sea level rise assessment projects that are currently underway; one along the coast (C-Smart) and one along the bayside (BayWAVE.) A sea level rise assessment and the impact of climate change on the hydrology of tributaries of Coyote Creek near the proposed project site must be done: one tributary along Browning Street is below the project site and will receive the majority of the run-off. The other tributary is directly parallel on Shoreline Highway. At the Alta Way Bridge these two tributaries are approximately 100 feet apart and they begin to narrow until they merge under 534 Browning Street. Buffer policies and creek/tributary protection studies are required.

This past winter the culvert at the intersection of Browning Street and Browning Court that captures the run-off from the proposed site of development on upper Alta Way could no longer accommodate the extraordinary run-off witnessed this year. The run-off found its way under Browning Street and travelled across towards the tributary where the road has begun to cave in. Environmental studies are required to assess the run-off and volume of seasonal springs, seasonal wetlands and underground springs and subsurface groundwater flow, which are extensive during the rainy season, before any new development can be contemplated or approved.

There are seasonal springs, wetlands, and riparian concerns because of the run-off directly into the tributaries of Coyote Creek. Additional seasonal wetlands could be indirectly affected by sedimentation and by modification of hydrology, which this large-scale development will surely do specific concerns.

The development of lower Alta Way in the 1999’s impacted the homes along the tributary from Alta Way Bridge, Palma, and Browning Street -- all the way to the condominiums on Browning Street at Northern Avenue. As a result of the run-off, Marin County installed an extensively engineered drainage system behind these condominiums. The build-out of upper Alta Way and drainage issues extend beyond the immediate area of Alta Way and impacts all homes along these tributaries, specifically along Browning Street and homes that surround the Alta Way Bridge.

Drainage problems and potential litigation can arise if the natural systems of surface and subsurface water flows from the proposed development site are not thoughtfully studied and engineered. For example: in 2010-2013, four property owners were involved in civil litigation regarding damage to downslope properties caused by surface and subsurface storm rain water run-off from the unimproved parcel APN 049-041-48, one of the 10 lots identified for proposed development.

Drainage calculations should include the run-off from the proposed build-out of not only the initial 10 parcels on Alta Way but the foreseeable additional 18 parcels and the extension of Fairview Avenue to Shoreline Highway, Blue Jay Way and the Cal-Trans drain which was installed this summer below Chamberlain Court which catches the water from Shoreline and above and flows into these tributaries.

Biological analysis and reports detailing the hazards of construction permeability, sediment, debris, soot and chemical run-off from the proposed construction site into the tributaries and damage to the habitat and ecosystems and loss of nutrients are of grave concern and a scientific report must be required. Biological Resource and Riparian biology reports for the entire area must be mandated.

5. Direct Impact of Hydrology/Engineering of Proposed Development On Homes Directly Adjacent to the Proposed Road Extension and Residential Vacant Parcel Identified in the Initial Study Notice

Individual and specific comprehensive Environmental reports including safeguards for homes directly adjacent and nearby the proposed Alta Way Extension and the 10 residential lots identified for development in the Initial Study Notice must be required.

Only 3 of the 10 lots identified in the Initial Study Notice for future development have slopes under 20%. The other parcels identified all have high slope percentages.

For example: APN 049-044-14 identified in the Initial Study notice for development has a slope of 45.35% and a lot size of 6300 sq. feet. This lot is adjacent to the proposed Alta Way road and sits above the home located at 547 Browning Street, APN 049-044-03 with a slope of 48.55%; the proposed home on such a steep hillside will add additional weight and impact drainage to the existing home(s) directly below.

a. Documentation, soils and hydrologic engineering reports must be required to determine if the proposed lots are indeed buildable based on slope and ratio to lot size in this zoning district.

b. A hydrology and geological report including engineering plans are required specifically to address the run-off, drainage system with calculations as well as a soils stability report pertaining to the homes adjacent to these initial 10 lots identified for development and the proposed extended road of Alta Way to Fairview. These homes are at the end of Alta Way, Browning Street, Browning Court, and Chamberlain, Everest and Denise Courts along Fairview Avenue.

c. The slopes of the 10 lots identified for initial development are:

Recent Approved County Initiated Merger:

Unmerged Lots:

The slopes of most of the lots in the approved subdivision do not conform to current requirements in the County building and zoning codes.

6. Public Safety, Health and Welfare

The FWTV has serious health concerns regarding the impact of this large-scale development on our Community. There are environmental and public safety health concerns regarding the grading, tamping, fill and construction of a 512’ road extension, undisclosed number, and length of 6’ high retaining walls as well as the construction of an initial minimum of 10 residential lots.

A comprehensive evidence based analysis must be performed to protect the public from hazards—seen and unseen, from construction, fumes, dust, soot and emissions, specifically carbon emissions of the excessive back and forth traffic of an undetermined number of construction vehicles and other large construction trucks over the course of a number of years to build and complete this proposed development.

Biological analysis and reports detailing the impact and potential hazards of construction debris, soot and chemical run-off from the proposed construction site on and into our homes is a priority. The proposed construction site will sit on a ledge of a steep hillside with homes in extremely close proximity and directly below it, in particular, homes along Browning Street.

The chemicals and sediment from products used to build the homes, roads and retaining walls will enter these homes and their backyards where residents presently have vegetable gardens, play structures and outdoor patios and may cause serious health issues for children, elderly, asthmatics and those with weak immune systems. Run-off will also find its way into the tributaries of Coyote Creek and can potentially cause irreparable damage to the watershed, riparian vegetation and ecosystem. These environmental and water quality impacts must be analyzed.

7. Noise Pollution

Our Community is concerned with the increased noise pollution from all aspects of construction, increased traffic and tree removal. A comprehensive acoustical study must be mandated and it should include the effects on the surrounding neighborhoods taking into consideration the noise pollution created by the proposed development, including noise pollution resulting from demolition, excavation and building.

8. Air Quality and Greenhouse Gas Emissions

Our Community is concerned regarding air quality as a result of construction and the impact on residents. A comprehensive report must be done to analyze the greenhouse gas emissions, fumes from construction vehicles, equipment, potential bio-hazards and carcinogens, and dust, as a result of construction for not just the grading of Alta Way road and 10 homes and for the entire WHOLE foreseeable development of this hillside—the two paper streets and the 28 vacant parcels. The BAAQMD has certain requirements for building a road in an area such as this, which would require significant earth moving and construction equipment. The proposed development plan does not meet those standards and therefore a comprehensive environmental report detailing compliance is required.

9. Current failing roadway infrastructure in close proximity to the proposed site of development

Our Community is concerned about the continued erosion of county maintained and non-county maintained roads in the area as a result of increased traffic and large construction vehicles combined with run-off.

A comprehensive roadway infrastructure report is required to review the impact of the current failing roads that exist in close proximity to the proposed development site. Currently:

  1. Shoreline Highway is eroding into the creek between Alta Way and Shasta in 3 places;
  2. Browning Street is eroding into the creek at Browning Court; and
  3. The Palma Bridge is failing.

An extensive infrastructure report should be required to determine the potential damage to the existing county maintained portion of Alta Way and the non-maintained portion of Alta Way road, caused during construction: how much wear and tear and erosion will be anticipated as a result of construction vehicles, bulldozers, cement trucks, contractor trucks etc., what damage will result in homes along Alta Way and how will the damage be remedied?

A geological engineering report and analysis should be required to review if the Alta Way Bridge can withstand the weight and constant traffic of large ton construction vehicles for the short and long-term build-out of upper Alta Way.

10. Utilities and Public Services

Our Community is concerned about the impact of the proposed development on utilities and public service. There is concern about how current utility infrastructure will be able to service an additional minimum of 10 to 28 future residences, when current utility infrastructure is already fragile and is often unable to provide adequate service.

Marin Municipal Water District: The developer must provide evidence that water flow, water pressure and hydrant pressure will be adequate.

Tam Community Services Sanitary District: The developer must provide evidence that the sewer system is adequate. The current antiquated sewer system of the area has documented clogging and seepage problems and can no longer accommodate current sewage for existing homes.

11. Animal and Plant Habitat

There are many species of trees on the 4 acres. Several species of native grasses have been identified including the purple needle grass, which roots extend to 20’ and are 100 years old. A vegetation report and analysis must be required because this historic land has never had an adequate environmental assessment since the creation of the 1892 Map of Marin County.

The 4 acres of historically untouched land is also filled with wildlife. There are various species of owls (some potentially protected species), Cooper hawks, red tail hawks and nests, foxes, coveys of quail and other bird species, snakes, raccoons, coyote and deer. A comprehensive environmental study must be required to assess the impacts of the destruction of this special habitat.

12. Archeological and Historic, Including Tribal, Cultural Resources

The proposed development site has been dormant since it appeared on the 1892 Official Map of Marin County. Prior to the map, the land belonged to Native American Indians. An archeology exploration report must be required.

13. Open Space Easements

A comprehensive report regarding the impact of the proposed development specifically addressing the environmental impact of the grading of Alta Way and building of retaining walls, which will border three dedicated Open Space Easements (OSE) is required. The covenants of the OSE must be honored. They must be protected from development as well as protected from any foreseeable and unforeseeable potential damage as a result of excavation and construction or anything that “would destroy any of its physical or scenic characteristics.”

14. Traffic, Traffic Flow, and Circulation

Traffic is of grave concern to all of us. The GGNRA estimates 1,000,000 visitors/vehicles a year pass the portal of Alta Way/Shoreline at the Loring Avenue hairpin turn. The Alta Way and Shasta Way blind turns are extremely dangerous when accessing and exiting Shoreline. The overflow of traffic and gridlock on Shoreline Highway during peak traffic hours, weekends and holidays can result in exceedingly long wait times to turn into neighborhood streets that service our homes on Alta Way, Sunnybrook and Blue Jay Way. We are requesting a recent and comprehensive traffic study of the congested Tam Junction, Shoreline Highway route to and from the GGNRA to gain a greater understanding of the future traffic impacts of this proposed large-scale development, including estimates of accidents and wait times on entering/exiting Alta Way.

A traffic study is also needed to assess the traffic flow and circulation and cumulative impacts of the opening of new streets and the commensurate changes in traffic patterns, and the joining of two paper streets and the impacts on Tam Valley as a whole; Alta Way extends to Shoreline Highway and Fairview Avenue extends from Shasta to Shoreline Highway—the long-range plan for development of Fairview Avenue for access to additional vacant residential lots must be addressed.

15. Land Use, Population & Housing Balance: Tamalpais Area Valley Community Plan and Marin Countywide Plan

Given the enormous resources that our Community and County have invested in the Tamalpais Area Valley Community Plan and Marin Countywide Plan we believe that the project should be reviewed to determine consistency with these two plans.

As stated in the Tam Community Plan, “The Tam Community plan has been adamant in maintaining the semi-rural character of the community as defined by its small town residential and commercial setting and the quality of the natural environment. New development shall be integrated harmoniously into the neighborhoods and geographic areas of the planning area in order to maintain their distinctive character.” It is imperative that we continue to “preserve the natural beauty and wildlife diversity of the tidal and season wetlands in the Planning Area through a program of acquisition and/or strict land use regulation.” Unless the developer applicant provides detailed information on the size, design types and character of the proposed development, this cannot be adequately addressed.

The impacts of the proposed 10 home development and the joining of two paper roads, the building of an initial minimum of 10 homes, and a foreseeable extension of Fairview Avenue to Shoreline Highway to access an additional 18 parcels on this antiquated subdivision cannot be overstated. The character of the neighborhood and the quality of life will be changed forever. A comprehensive Environmental Impact Review (EIR) in accordance with the requirements of CEQA will help identify those impacts and indicate whether they can or cannot be mitigated.

The TDRB with their wealth of experience, knowledge and foresight, appropriately stated in their April 20, 2016 letter to Brian Crawford:

“A piece-meal development approach will have cumulative impacts on the surrounding community, people that live on the present Alta Way, and the 14 streets, bounded by this development will be impacted for years.’’

This letter incorporates by reference previous public comment letters from FWTV to various County Officials and are included in Attachments A, B, C, D related to the Brown Design Review Project and the Initial Study, Alta Way Extension.

We also kindly ask that we receive acknowledgement that this letter was received and will be included in the public comment file for the Public Scoping Session of the Alta Way Extension Project, Initial Study.

Respectfully submitted,

The Executive Committee, Friends of West Tam Valley - /s/ Lee Budish, /s/ Charles DeLacey, /s/ Richard Hayes, /s/ Michael Burns, /s/ Roger Brown, /s/ Marilyn Filbrun, /s/ Ren Klyce

Attachment A: March 10, 2016, FWTV/GVLCFNA to County Officials

Attachment B: May 22, 2016, FWTV to Alicia Giudice, Project Manager

Attachment C: September 12, 2016, FWTV to Kate Sears

Attachment D: March 6, 2017, FWTV to Board of Supervisors


[1] Data obtained from Marinmaps.

Attachments A, B, C and D (pdf 214.63 KB)