Project Description
The Marsh Creek Corridor Multi-Use Trail Feasibility Study was initiated to assess the opportunity to develop a new multi-purpose recreational facility along the Marsh Creek and Marsh Creek Road corridor. As ultimately envisioned, the trail would create a new major non-motorized thoroughfare for expanded commuting and recreational opportunities. The purpose of the trail is to provide a safe, useful, and enjoyable transportation corridor that supports multiple forms of non-motorized travel, including pedestrians, bicyclists, and equestrians.
Background
January 2019, County staff and Fehr & Peers (consultant) initiated the study. A summary of tasks staff and the consultant have been engaged in include:
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Receiving public input via web-based mapping tool.
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Data collection and base mapping.
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Public outreach events along the corridor and virtually.
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Define study goals and develop improvement concepts.
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Convened Technical Advisory Committee* (“TAC”) meetings.
*TAC consists of staff representatives from Clayton, Concord, Brentwood, East Bay Regional Park District, Save Mt. Diablo, State Parks as well as various County staff.
Public Outreach
The study benefited from public input through a series of public outreach strategies that included the formation of a technical advisory committee, pop-ups events at public locations for community members to provide feedback, direct outreach to property owners, field visits, public workshops, and online engagement tools.
Generally, feedback provided through these channels was used to develop initial trail alignments, revise these alignments to reduce impacts to property owners, and ultimately arrive at a set of recommendations for trail design, phasing, and implementation considerations for Marsh Creek Trail.
September 2019, initial public outreach efforts included attendance at two Farmer’s Markets; one held in Brentwood and one in Clayton. At both events, consultants and County staff occupied an informational booth with handouts, flyers and other visuals to help promote the study.
December 2019, County staff and the consultant team held a project update meeting at the Clayton Library where attendees were provided the project background, status update, and next steps followed by a questions and answer session.
November 2020 and November 2021, County staff and the consultant team held well-attended (average 30+ participants) virtual public workshops. Most attendees were Marsh Creek Corridor property owners but representatives from other agencies were also in attendance (County staff, Save Mt. Diablo, State Parks, CalFire, bicycle advocacy groups). These meetings with property owners were critical as they provided firsthand insight and various concerns with the introduction of a potential public trail, a brief summary of which includes: increased risk of wildfire/arson, crime, property damage, negative impact to cattle ranching activities, and general concerns about lack of enforcement of hours of operation and trespassing. Property owners were also concerned about eminent domain. Staff does not recommend eminent domain be invoked for any potential phases of the Marsh Creek Corridor public-use trail.
An online public engagement webmap tool was created to help inform the general public of the study’s purpose, progress and resources, and gave an opportunity to provide feedback. An online web-map was used to gather specific feedback from the public regarding potential trail alignments. The tool was useful in gathering information regarding any potential constraints or concerns seen by the corridor’s users and residents, and the information received helped inform the next iteration of trail alignment alternatives.
Draft Study
The draft study was published for public review on October 24, 2022.
The draft study summarizes the data collected in the technical memos and defines the study vision and goals based on feedback from the public engagement process and TAC.
The goals of the study include:
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Evaluate the potential for a multi-modal trail providing connectivity from the trail system in the City of Clayton to the Round Valley Regional Preserve
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Conduct extensive public engagement to understand the needs and concerns of groups including residents, advocacy groups, and rural and disadvantaged communities
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Develop a trail alignment that minimizes impacts to private property and retains privacy for residents
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Identify restoration opportunities along Marsh Creek to occur in conjunction with trail development opportunities
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Assess environmental constraints and impacts that may constrain trail development
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Identify a phased approach for implementation
The public review period ended on Friday, November 18, 2022. The draft study will be revised based on comments received over the public review period and a final study will be presented to the Board of Supervisors for consideration in early 2023.
Conceptual Trail Alignments
The development of potential trail alignments for the purposes of identifying opportunities and constraints was shaped by a multitude of factors, which included:
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A public lands first approach, beginning with identifying opportunities to link sections of land currently under public control, or in conservation through Save Mount Diablo
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A strong desire from the public to minimize encroachment upon private property, except where necessary to link parcels of publicly dedicated land
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An alignment that roughly follows the curvature of the creek and Marsh Creek Road
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Minimize the number of roadway crossings to reduce user exposure to vehicular traffic
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Consideration of an on-road option in some locations to accommodate road cyclists and to avoid areas where significant disruption to private lands or environmental settings would otherwise occur
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Use of existing fire roads, access roads, and trail segments where possible to minimize impacts to undisturbed land
Implementation of an approximately 15-mile trail would likely need to occur over a long period of time, as funding and land for the trail become available. However, it is also anticipated additional public outreach and subsequent refinements to the trail alignments will be necessary (based on nuanced topographical, environmental, and construction considerations) before any portion of the trail concept can be moved to an implementable project.
Phasing & Cost Estimates
The approximately 13-mile study corridor was divided into three sections with each section presenting various considerations for implementation. Further, a phased approach will make implementation more manageable if an implementable project were eventually developed. A map depicting this conceptual phasing is provided in Figure 6-1 of the draft study.
Cost estimates were based on the Caltrans six-page cost estimate format for each of the three trail segments (see feasibility study Appendix D). These are high-level planning cost estimates where several assumptions were made, like the item quantities for construction materials which would fluctuate over time and as trail concepts are refined. Cost estimates also do not include right of way acquisition or cost escalation factors. These cost estimates merely serve as a beginning frame of reference for what a facility like this may cost, which is a necessary step in any feasibility study exercise.
Phase 1: Clayton City Limits to Clayton Ranch (5.7-miles, estimated cost $19.1 million)
The section of trail proposed for initial implementation would connect to existing bicycle and pedestrian facilities at the Clayton city limits and stretch approximately 5.7 miles to the east. The trail is recommended to connect to lands held by the East Bay Regional Parks District (EBRPD), which begin approximately 2.3 miles from the Clayton City limits. The property, known locally as Clayton Ranch, is planned for future recreational amenities including public access and hiking trails.
Phase 1 would allow for a more immediately usable section of trail that links public lands to existing bike and pedestrian facilities. Connecting to planned projects at Clayton Ranch would reduce the overall cost and effort for implementation, while also creating new access to recreational amenities. This section of the overall project also has the highest amount of land held publicly or by Save Mount Diablo, reducing the need for right-of-way acquisition. It is anticipated that the portion of the trail within Clayton Ranch would be developed by EBRPD.
Phase 2: Clayton Palms to Round Valley Regional Preserve (4.7-miles, estimated cost $7.1 million)
Similar to Phase 1, the second phase of the project would leverage existing recreational amenities at Round Valley Regional Preserve. With a length of approximately 4.7 miles, this section of trail would extend from Round Valley on the southern side of the roadway, cross at Deer Valley Road, and end just west of the Clayton Palms community, increasing recreational opportunities for residents of that community. The trail would also provide better access to Round Valley by bicyclists using the existing bike lanes on Deer Valley Road, which is a popular cycling route that connects to Brentwood.
Implementing this section of trail will require sensitivity to private land ownership given that most of the proposed alignment, while following Marsh Creek, crosses through multiple privately owned properties. As such, two alignments are proposed, with one focused on on-road improvements along Marsh Creek Road to use public right-of-way and minimize environmental impacts, particularly in the area just east of Deer Valley Road. A second proposed alignment would veer away from the roadway to maintain the preferred off-road nature of the facility, but should be considered a long-term option as land in that area becomes available for a trail easement by willing sellers. This section of trail also requires the least amount of physical disruption to the environment, as the terrain begins to flatten and fewer retaining walls will be required.
Phase 3: Dark Canyon (4.7-miles, estimated cost $16.5 million)
The third phase of the project will link both prior segments of trail to create a continuous facility from Clayton to Round Valley Regional Preserve. Running approximately 4.7 miles through the “Dark Canyon” area of the corridor, this section of trail features the greatest number of physical constraints on the alignment due to steep terrain and will require the trail to run in close proximity to the creek on the south side of Marsh Creek Road, with a crossing back to the north side at either end of the section.
Ownership is mixed within the section. Several small parcels are held by Save Mount Diablo, and as such the trail alignment seeks to connect between those areas to minimize impacts on private land. A high number of retaining walls will likely be required to provide a usable trail at even a minimum trail width. Given the need to run the trail adjacent or near to Marsh Creek, this can also provide an opportunity for trail implementation and creek rehabilitation efforts to occur simultaneously.
Operation and Maintenance
If a project were to move forward an important point of discussion will be how to operate and maintain a new trail facility. Section 6 of the draft study discusses potential management and revenue options. Establishing this management and funding structure will require a coordinated effort among the Marsh Creek Corridor stakeholders and would be necessary before deciding to implement trail concept alternatives. |