CALL TO ACTION -“NO COST PROACTIVE SAFETY IMPROVEMENT PLAN”
CALL TO ACTION – CONTACT EDDIE GUARACHA, SUPERINTENDENT DIABLO RANGE – eddie.guaracha@parks.ca.gov – Immediately implement the “NO COST” Proactive Safety Improvement Plan
Eddie Guaracha December 20, 2021
Superintendent, Diablo Range District
California State Parks
(Sent via e-mail)
Re: South Gate Road Exceptional Hazard Area – Park Boundary to Kiosk (2.5 miles)
Mount Diablo State Park
Dear Mr. Guaracha,
In the last seven months three Park visitors; Gary Spinella (May 30, 2021), Ron Wolfe (July 3, 2021) and Rick Edmondson (December 1, 2021) were involved in separate incidents with a motor vehicle and suffered serious injuries while descending on a bicycle on this dangerous section of South Gate Road in Mount Diablo State Park (MDSP). We urge you to take immediate action by implementing the “NO COST Proactive Safety Improvement Plan” described below. The NO COST Plan will improve safety for all Park visitors on South Gate Road from the Park entrance to the Kiosk (2.5 miles).
1. Issue Citations to drivers for passing cyclists on blind curves, crossing over solid yellow lines, driving for extended distance in the on-coming lane and to cyclists for speeding per the California Vehicle Code (CVC). According to State Park records, Park Rangers rarely issued citations to drivers for passing cyclistson blind curves, crossing over solid yellow lines and/or driving for extended distance/time in the downhill lane as they pass (2010 to July 2021).
2. Establish a semi-permanent Park Ranger Presence on the most dangerous section of road on MDSP – South Gate Road from the entrance to the Kiosk (2.5 miles). Especially on weekends.
3. Conduct regularly scheduled patrols focused on issuing citations to drivers per #1 above.
4. Periodically position Park Ranger vehicles at key locations on South Gate Rd from entrance to the Kiosk.
5. Require Park Aides at the South Gate Kiosk to read the “MDSP Verbal Motorist Safety Advisory” to All drivers. Kiosk attendants were required in January 2018 to give the Motorist Safety Advisory to every driver entering the Park.
6. Conduct and publish a Citation Audit.Review all citations issued to Park visitors in Mount Diablo State Park from 2010 to present; for passing on blind curves, crossing over solid yellow lines and/or driving for extended distance/time in the downhill lane as they pass and speeding.
7. Approve Warning Letters for MDSP Rangers to issue per the California Highway Patrol standard. Over the years, significant numbers of Park visitors have reported aggressive motorists to Park Rangers. The Park Ranger usually says “there is nothing I can do unless I see it.” As a result, the Park visitor (cyclist) usually rides away still angry with the motorist who nearly hit him and disillusioned with the Park Ranger for his lack of concern for his safety. We believe it is time to break this cycle and implement a MDSP Warning Letter Policy similar to the CHP Warning Letter Policy. This would provide Park Rangers with an innovative and effective prevention tool to educate motorists, reduce aggressive driving behavior, near-miss collisions and actual collisions between Bikes vs. Vehicles. CHP Warning Letters are used throughout the CHP Golden Gate Division and Contra Costa County. They have proven extremely effective in reducing unsafe driving behavior.
Why are we recommending the Park take this action today?
We believe there is a high likelihood of another bike vs vehicle collision on this exceptionally hazardous stretch of road resulting in another serious injury or fatality involving a Park visitor. Here are eight compelling reasons why:
- There is significant evidence from Traffic Collision Reports, Park officials and numerous videos of motorists frequently crossing the solid double yellow line to pass cyclists on blind curves and then continuing to stay for an extended distance/time entirely in the on-coming lane. Park Rangers and District officials have been aware of the unsafe motorist behavior and this dangerous section of South Gate Road for years. When drivers were asked, why did you drive almost entirely in the on-coming lane as you traveled up the road? They often said; “I was afraid of the edge,” “it drops off,” “it’s steep and I’m afraid,” “I’ve never been here before” or “I didn’t know there were so many bicycles.”
- Near-Miss Bike vs Vehicle Collisions are occurring weekly if not daily. At the Bike Turnout Ceremony in Mount Diablo State Park on August 23, 2021 (pictured above), most hands were raised when cyclists were asked. Please raise your hand if you ever had a vehicle pass you on a blind curve.
- The high number of vehicles and bicycles: 60% of All vehicles traveling up and down South Gate Road are bicycles.
- Analysis of recent Bike vs Vehicle Collisions: on December 1, 2021, July 3, 2021 and May 30, 2021, Park visitors Rick, Ron and Gary were seriously injured in three separate bike vs vehicle collisions. Apparently, no Park or District official has called them to express any compassion or empathy for the injuries they suffered as Park visitors.
- Analysis of 17 Bike vs Vehicle Collisions (Traffic Collision Reports): South Gate Road, entrance to Kiosk (2.5 miles). Every week drivers pass cyclists unsafely at or near one of the 22 blind curves as they travel up this dangerous section of road. Since 2015, we have offered to partner with MDSP/district officials to analyze All Traffic Collision Reports. Unfortunately, Park officials have refused to collaborate with us or conduct/share their analysis. As a result, we have been compelled to conduct the analysis and publish the results. District officials should analyze All Traffic Collision Reports and publish a report (2010 to present).

6. Cyclist and Motorist Surveys Demonstrate There is a Safety Issue: Since 2015, we have offered to partner with MDSP/district officials to conduct surveys of cyclists and motorists. Unfortunately, officials have refused to collaborate with us or even conduct their own surveys. As a result, we were compelled to conduct the surveys. The results are as follows:
A recent video survey showed that 25% of the vehicles crossed the solid double yellow line, traveled for an extended distance/time in the downhill lane and passed cyclists on the third blind curve near the entrance of South Gate Road. According to Park visitors; “we’ve rarely seen a Ranger on South Gate Road from the entrance to the Kiosk.”
According to 128 cyclists surveyed on January 1, 2018: 29% of the reported 1,161 bike passes were unsafe.
Based on video surveys, every year hundreds of drivers pass cyclists on blind curves.
In 2018, 100 drivers were asked the following questions:
Is this your first visit to Mount Diablo? Majority said – Yes
Did you cross solid double yellow lines to pass bicycles? 95% said – Yes
Did you receive a Verbal Motorist Safety Advisory as you entered the Park? Majority said – No
Did you know there would be so many bicycles on the roads of the Park? Majority said – No
Did you know the roads are narrow and winding, with lots of blind curves? Majority said – No
7. Analysis of Motorist and Cyclist Citations Suggest Insufficient Law Enforcement: According to CA State Parks Statistical Reports, there have been over a million-motor vehicle/bicycle – based visitors from 2010 to July 2021. According to the Supervising Ranger: “We have right around a half a million people per year that visit Mount Diablo State Park.” (Save Mount Diablo video, Oct 14, 2021)
Park Rangers issued only 325 Citations


- 8. Analysis of Law Enforcement Staffing Suggests Room for Improvement: The Park’s law enforcement consists of a Public Safety Officer (Ryen Goering), Supervising Ranger (Cameron Morrison) and five Park Rangers (Scott Poole, Jordan Fenwick, Tristan McHenry, John Baxter and one vacant position). The Staff Interpreter is Sharon Peterson. Typically, two Park Rangers are scheduled to work 0700 hrs. to 1400 hrs. and two Park Rangers are scheduled to work 1400 hrs. to Closing/Sunset. The supervising Park Ranger usually does not work on Friday and Saturday. Ranger training typically consists of Weapon familiarization/qualification (AR-15 Rifle, 40mm Pistol & Shotgun), Defensive Techniques and First Aid. There is usually no law enforcement presence on Mount Diablo when Rangers are engaged in firearm training at the Richmond Rod & Gun Club. Apparently, collisions with serious injuries to Park visitors have occurred when Rangers have NOT been available to assist.
We urge you to immediately implement the “NO COST Proactive Safety Improvement Plan.” We believe, there is a high likelihood of another bike vs vehicle collision on this exceptionally hazardous stretch of road resulting in another serious injury or fatality involving a Park visitor.
Sincerely, Alan Kalin, COL, USA (Ret.), President Mount Diablo Cyclists, Linda Kwong, Vice-President Mount Diablo Cyclists, Bruce Bilodeau, Coach San Ramon High School Mount Bike Club, Jeff Eorio, Director Recreation Department (Retired), City of San Ramon, Mark Dedon, Charlie Wills, Mark Dedon, Cyclists recently hit by vehicles on Mount Diablo – Gary Spinella (May 30, 2021) and Rick Edmondson (December 1, 2021)
CC: State Senator Steve Glazer, Assemblymember Rebecca Bauer-Kahan, Teresa Gerringer, Mayor of Lafayette, Newell Arnerich, Mayor of Danville, Allen Shields, Chief Danville Police Department, Ben Alldrift, Chief Lafayette Police Department, Tara Lynch, Chief Counsel, Department of Parks and Recreation, Bob Burns, Vice-President TREK Bicycle and Dan Borenstein, Columnist/Editorial writer, Mercury News & East Bay Times
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