65 Bike vs Vehicle Collisions: 2002 to Oct 2022

We are currently reviewing ALL data to determine the correct number of Bike vs Vehicle Collisions. According to California State Parks, there has been 17 Bike vs Vehicle Collisions from 2010 to 2021. Since 2014, we have repeatedly requested to collaborate with State Parks to determine the correct number of Bike vs Vehicle Collisions. (Unfortunately, California State Parks has NOT been willing to work with us to determine the correct number of Bike vs Vehicle Collisions on the roads of Mount Diablo State Park)

According to over 10 years of research and analysis of California State documents received per Public Records Act (PRA) requests:

  • Apparently, there has been 65 Bike vs Vehicle Collisions on the roads of Mount Diablo State Park from 2002 to October 12, 2022.
    • South Gate Road = 28 Bike vs Vehicle Collisions
    • Summit Road = 24 Bike vs Vehicle Collisions
    • North Gate Road = 13 Bike vs Vehicle Collisions
  • For years, Park Rangers would conduct the investigations and complete the Traffic Collision Report (CHP-555). The Supervising ranger reviewed the TCR and then filed it in a cabinet in Clayton. Apparently, there was very little analysis of causes and NO recommendations to prevent future Bike vs Vehicle Collisions and the resulting injuries to Park visitors.
  • Several years ago, the CHP at the request of State Parks begin conducting ALL Bike vs Vehicle Collision investigations and completing the Traffic Collision Report (CHP-555).
  • In April 2015, the MDSP superintendent produced the “Traffic Accident Data, 2005 to 2015.” A brief one-page document with NO analysis of cause(s) or effort to identify the commonality factors (document at bottom of this report). He did NOT make any recommendations to prevent future collisions or injuries to Park visitors.
  • Prior to 2016, numerous cyclists/Park visitors were being injured, some very seriously, and State Parks were doing NOTHING to understand the causes and prevent future collisions and injuries.
  • According to a Public Record Act request; “Prior to 2015, the California Highway Patrol – Contra Costa Area did not retain collision reports digitally. All collision reports prior to 2015 have been purged and/or there are no records.” (CHP Commander, D.G. Seaman, Captain, Sept 11, 2019)
  • We have found NO evidence of a citation ever being issued to any of the 60+ drivers involved in the Bike vs Vehicle Collisions.
  • We have found NO evidence of California State Parks ever implementing any Safety Improvements from 2002 to 2016 to reduce Bike vs Vehicle Collisions and prevent injuries.

Over the years, we have submitted numerous Public Records Act (PRA) requests to California State Parks requesting the Traffic Collision Reports (TCR) (CHP-555) and the Public Safety Reports (DPR-385). For the last several years, the California Highway Patrol (CHP) has investigated the Bike vs Vehicle Collisions on Mount Diablo and completed the TCRs, NOT MDSP Park Rangers. As a result, additional PRA’s were submitted to the CHP to receive the TCRs.

The CHP Statewide Integrated Traffic Records System (SWITRS) database and statistical reports were also analyzed and cross-referenced with All public documents. In addition, we recently received the Mt. Diablo SP Reference Map which identified 17 Bike vs Vehicle Collisions from 2010 to 2021. The map was provided by the Superintendent of Diablo Range District. The map identified only 17 of the 45 Bike vs Vehicle Collisions that occurred from 2010 to 2021. 

The following is a list of 65 Bike vs Vehicle Collisions:

  1. 6/5/2002 Wednesday (2025hrs), Summit Road, Motorist - CVC 21751-Improper pass on Blind Curve, Male (45yrs), Serious Injury.  CHP-SWITRS
  2. 9/29/2002 Sunday (1100hrs), Summit Road, CVC: 21750-Improper pass, Broadside, Male (44yrs), Injury.  CHP-SWITRS 
  3. 11/16/2003 Sunday (1410hrs), South Gate Road (distance; 8976ft), Blind Curve, Male (46yrs), Injury.  CHP-SWITRS 
  4. 6/27/2004 Sunday (1200hrs), Summit Road – Sunset Picnic, Motorist Improper Pass-CVC 21751, Blind Curve, Male (54yrs), Injury.  CHP-SWITRS 
  5. 9/27/2004 Monday (1145hrs), Summit Road (distance; 3168ft), Motorist Wrong Side, Sideswipe-CVC21650, Male (36yrs), Injury.  CHP-SWITRS 
  6. 1/30/2005 South Gate Road, South Gate Road (SG2) Mt. Diablo SP: Reference Map provided by Eddie Guaracha, Superintendent Diablo Range District.
  7. 3/12/2005 Saturday (1100hrs), Summit Road (distance 3168ft.), Motorist on the wrong side of the road – CVC 21650, Broadside, Male (33yrs), Injury.  CHP-SWITRS 
  8. 4/9/2006 Sunday (1315hrs), North Gate Road (secondary road; Area of, Male (44yrs), Sideswipe, Injury.  CHP-SWITRS 
  9. 6/11/2006 Sunday (1100hrs), South Gate Road (distance 0ft), Driver slowing, Rear End Collision, Male, Injury.  CHP-SWITRS 
  10. 11/25/2006 Saturday (1510hrs), Summit Road (distance 461ft), Point Picnic, Male (28yrs), CVC: 21751, Improper Pass & Sideswipe, Injury.  CHP-SWITRS 
  11. 3/15/2008 Saturday (1130hrs), South Gate Road (distance 80ft south of 1mile marker), Motorist CVC: 21750 -Improper Pass & Sideswipe, Male (47yrs), Injury.  CHP-SWITRS 
  12. 10/6/2008 Monday (1205hrs), South Gate Road (distance 8448ft -North), Motorist CVC21650 – Wrong Side – Head-On Collision, Male (40yrs), Injury.  CHP-SWITRS 
  13. 3/26/2008 Wednesday (1245hrs), South Gate Road, (distance 10ft -North of the Service Yard Road), Motorist CVC 21750 -Improper Pass & Sideswipe, Male (56yrs), Injury.  CHP-SWITRS 
  14. 8/3/2008 Sunday (1140hrs), Summit Road (distance 0ft) Secondary Rd: Junction, Bicycle-CVC: 21650-Wrong Side, Unsafe Turn, Male (51yrs), Injury.  CHP-SWITRS 
  15. 1/17/2009 Saturday (1415hrs), Summit Road (distance 528ft -South of Toyon Dr.), CVC:22350-Unsafe Speed, Deepinder Singh, Male (42), Injury.  CHP- SWITRS BELOW  Open this Link to View Deepinders Collision Video Story
  16. 7/11/2009 Saturday (1045hrs), South Gate Road (distance 4646ft/.88miles), CVC: 22350, Unsafe Speed-Sideswipe, Hit and Run, Male, Injury.  CHP-SWITRS 
  17. 8/2/2009 Sunday (1018hrs), South Gate Road (distance 4ft), CVC: 21650, Wrong Side, Male(37yrs), Injury.  CHP-SWITRS 
  18. 1/9/2010 Saturday (11:50 am) 1.7 miles up South Gate Road, 1 mile from South Kiosk, Blind Curve Passing Cyclist (1 mile down), Male (29yrs) & Male (46yrs), (REACH Helicopter), Injuries. Public Safety Report: (Event# SRFPD#158/CHP 01-43
  19. 1/23/2010 Saturday (1500hrs), South Gate Road (distance 9240ft-North of SG Boundary/just below 1.75 miles up at Blind Curve, .7mile North of Junction Ranger Station, CVC: 22350-Unsafe Speed-Rear End, Male (58yrs) Injury. TCR#210201223 & CHP-SWITRS
  20. 5/29/2010 Saturday (1010hrs), North Gate Road near School Bus Curve (distance 3696ft -North of Junction), CVC: 22350-Unsafe Speed - Read End, Male (46yrs), Injury.  TCR# 210209556 & CHP-SWITRS
  21. 6/24/2010 Thursday (1800hrs), .2 miles south of SG 1.5, N37.84556 / W121.92729, Elevation 1253ft, Blind Curve Passing Cyclist, CVC: 21751, CVC: 21752(a), CVC: 12814.6(D)(5b-1B), Male (32yrs), Injury. TCR# PS210211619
  22. 1/9/2010 South Gate Road, South Gate Road (SG2) Mt. Diablo SP: Reference Map
  23. 1/8/2011 Saturday (1220hrs) .125 miles NE of SG road marker 1.50, .123miles SW of 1.75mile marker, or .4 below Kiosk, Fault of Cyclist! Cyclist hit the vehicle, wide turn on Blind Curve, (between the 1.75 and 1.5mile markers) crossed the center line, CVC: 22350, Male (50yrs) Injury.  TCR# 211200349 & CHP-SWITRS
  24. 3/17/2011 Thursday (1500hrs), South Gate Road, below South Gate Kiosk, .4 miles below kiosk, GPS: W 37.841431 N121.931702, CVC: 21650, Blind Curve, David Dalton, Male (51yrs), Injury.  Public Safety Report (Event# 211203997) Open this Link to View Daves Collision Video Story
  25. 5/19/2011 South Gate Road, South Gate Road (SG2) Mt. Diablo SP: Reference Map Open this Link to View Morgans Collision Video Story
  26. 5/21/2011 Saturday (1300hrs), Summit Road (distance 0ft), Near Junction, Blind Curve, CVC: 21751 “no vehicle shall be driven to the left side of the center on the roadway in overtaking and passing another vehicle proceeding in the same direction,” Male (22yrs), Injury. TCR# 211208016 & CHP-SWITRS BELOW
  27. 6/18/2011 Saturday (0857hrs) 1.38 miles up South Gate Road, 1 mile south of entrance station, N37.84370 / W121.93581, elevation 1,170ft, Blind Curve Passing Cyclist, Male (52yrs), Injuries, (CALSTAR- Helicopter). Public Safety Report (Event# 211210667)
  28. 6/19,2011 Sunday (1250hrs), South Gate Road (distance 1985ft- South), near the entrance of Service Yard, Blind Curve, Vehicle in his lane as he was descending, CVC: 21751-Improper Pass & Sideswipe, Male (51yrs) & Male (58yrs) Injury.  TCR# 211210511 & TCR# 211210754 & CHP-SWITRS 
  29. 7/1/2011 Friday (1713hrs), Summit Road, 1mile east of North Gate Road, Curve at Juniper Campground Parking lot, CVC: 21801(a.) Failed to yield the right of way, William Babcock, (Male), Injury.
  30. 8/12/2011 Friday (1210hrs), North Gate Road (distance 0ft), Male (46yrs), Injury.  CHP-SWITRS
  31. 1/1/2012 Sunday (1121hrs), North Gate Road, .11miles North of Summit Road, Blind Curve, CVC: 21750-Unsafe Passing Movement, CVC: 21751- Passing Without Sufficient Clearance, Driver “passed 10 bicyclists,” Male (58yrs), Injury. TCR# 212200097 & CHP-SWITRS
  32. 1/11/2012 Summit Road, South Gate Road (SG2) Mt. Diablo SP: Reference Map
  33. 4/21/2012 Saturday (1150hrs), Summit Road at Junction Picnic Area, CVC: 21801(a), Vehicle turned left into Junction Picnic Area entrance and hit the descending cyclist Sabrina David?, Female (33yrs), Injury. Public Safety Report (Event# 212206951)
  34. 5/6/2012 Sunday (1604hrs), approx. 1.5 miles south(below) of Kiosk South Gate Road, CVC: 21750, Unsafe Passing, Blind Curve Passing Cyclist, Male (44yrs), Injury. Public Safety Report (Event# 212208148)
  35. 5/15/2012 Tuesday (1115hrs), North Gate Road, 202ft North of Burma (fire) Road Intersection, 2.95miles South of MDSP Boundary gate (North Gate), GPS: N 37.87670 – W 121.96252 (Elevation: 964’), CVC: 21750-Unsafe Passing, Blind Curve, Male (61yrs), Injury.  TCR# 212208673 & CHP-SWITRS 
  36. 6/26/2012 Tuesday (1514hrs), Summit Road, Devil’s Elbow, CVC: 21480(a), car in lane Blind Curve, Richard Starbird, Male (33yrs), Injury. Public Safety Report (Event# 212212226)
  37. 9/15/2012 Sunday (1100hrs), North Gate Road, 4.25miles North of North Gate Road, Blind Curve, CVC: 21650-Driving Left of Center-Crossing Over into Opposite Lane, Blind Curve, Male (26yrs), Injury.  TCR# 212220008 & CHP-SWITRS
  38. 10/27/2012 Saturday (1420hrs), North Gate Road,” location unknown,” Driver made “U-turn,” CVC: 21801(a) yield when making a U-turn until reasonably safe,” Male (48yrs), Injury.  TCR# 212222373 & CHP-SWITRS 
  39. 11/4/2012 Sunday (1043hrs), North Gate Road near Diablo Ranch, North Gate Road, near Diablo Ranch, GPS: N 37.86584 – W 121.94387 (Elevation: 1,539’), Blind Curve, Male (45yrs), Injury. Public Safety Report (Event # 212222770)
  40. 3/16/2013 Friday (1300hrs), South Gate Road, .03miles south of the entrance to Rock City, CVC:21752(a)-Driving left of center with a limited view by blind curve, near Rock City Female (28yrs), Injury. TCR# 213203720 & CHP-SWITRS
  41. 1/2/2014 Saturday (1022hrs), North Gate Road, North Gate Road, 1.25miles west of Summit Road, CVC: 22350 (Unsafe Speed) Driver, Diablo SP: Reference Map, Male (33yrs), Injury, CalStar Helicopter
  42. 1/25/2014 Saturday (1022hrs), North Gate Road, 230ft South of Mile Mark 5.25 or 1.25miles West of Summit Road, Blind Curve, CVC: 22350, Mr. Peck, Male (60yrs), Reach Medivac Helicopter, Injury. TCR# 214-10-2192 & CHP-SWITRS 
  43. 7/4/2014 Friday (1015hrs), Summit Road, approx. 50ft North of (above) Green Ranch (Fire) Road, Blind Curve, William Clayvielle, Male (27yrs), Injury, CalStar Helicopter. TCR? Public Safety Report (Event# 140704NOR-0040) Open this Link to View Wills Collision Video Story
  44. 9/13/2014 Saturday (1217hrs), Summit Road below (south of) Diablo Valley Overlook, 2.25miles north of Junction Ranger Station, Blind Curve, GPS: N 37. 5234 – W 121, Van in lane (Unsafe Passing) (Left of center), CVC: 21751, Blind Curve, Male (41yrs), Injury. TCR# 140911NOR-0070 & Public Safety Report (Event# 1409NOR-0070) & CHP-SWITRS
  45. 11/9/2014 Sunday (0950hrs), Summit Road, 2.5miles North, above Juniper Campground, Blind Curve, GPS: N 37.87513 – W 121.92905 (Elevation: 3,025’), CVC: 22350, Unsafe Speed for Conditions, Mr. Carlos Ortiz, Male (49yrs), Injury. TCR# 141109NOR-0037) & CHP-SWITRS
  46. 7/5/2015 Sunday (1100hrs), Summit Road, distance 1.70 North of Junction Ranger Station, GPS: N 37.87149 – W 121.92664 (Elevation: 2,676), CVC: 21751 (Passing without Sufficient Clearance), Blind Curve, Paula Nepomuceno (photo below), Female, Injury.  CHP-SWITRS Open this Link to View Paula’s Video Story
  47. 8/22/2015 Saturday (1730hrs), South Gate Road, Near Service Yard Road, Driver (vehicle photo below) Passing ascending cyclist on Blind Curve and hitting a descending cyclist, Victor Lorenc (photo below), Male (55yrs), Injury.  Open this Link to View Victor's Video Story
  48. 9/26/2015 Saturday (0943hrs), North Gate Road, 1.5 miles below Junction Ranger Station, Driver passed ascending cyclist and hit descending cyclist, CVC 22107, Shannon Stepper, (photo below) Female, Injury. Open this Link to View Shannons Video Story  Open this Link to View the Fire Department & Ambulance at Shannons Bike vs Vehicle Collision
  49. 10/2/2015 Friday (1158hrs), Summit road, distance 3696ft North of Junction, .7miles North of Junction Ranger Station, CVC: 21752, Wrong Side, Head-On Collision, Blind Curve, Linda Kwong, (photo below) (Female (53yrs), Injury. CHP-SWITRS Open this link to view Linda’s Video Story
  50. Open this Link to View CH 7 News Investigates Bike vs Vehicle Collisions: Mount Diablo (Nov 23, 2015)
  51. 10/16/2015 Friday (1430hrs), Summit Road, 2640 ft North of South Gate Road, Lat: 37.863013 – Long: 121.927749, Blind Curve, Xou Saetern, Male, Injury, CalStar Helicopter. TCR# 9320-2015-0853
  52. 7/1/2016             Friday (1529hrs), 1.7 miles up South Gate Road, Lat 37.841416 /Long 121.931839, Blind Curve, Kevin Sawchuk, Male (56yrs), Injury. TCR# 9320-2016-7037.  A Park Ranger allowed the driver to continue driving the vehicle (photo below) after the collision to his campsite at Juniper Campground, several miles up South Gate and Summit Roads.  Open this Link to view Kelvin's Video Story    Open this Link to View the Vehicle Parked at Juniper Campground
  53. 10/1/2016 Saturday (1106hrs), South Gate Road, Grapevine Picnic Area, curve, N 37.6409/W 121.93267, .26 miles south of the Junction GPS: N 37.86409 – W 121.93267, CVC: 22350, Blind Curve Passing Cyclist, Bruce Wright, (Male) Injury. CHP-SWITRS
  54. 12/5/2017 Tuesday (1345hrs), Summit Road, Near/Above Muir Picnic Area, blind curve, Charles Edward Wills III, Male (67yrs), CVC: 22350, Blind Curve, Vehicle in his lane as he was descending, Injury.  TCR(# 171205NOR0057 & CHP-SWITRS BELOW Open this Link to View Charles Collision Video Story
  55. 3/27,2018 Tuesday (1831hrs), North Gate Road, Blind Curve, Garrett Lew, Male, Injuries. According to the Traffic Collision Report# 180327NOR-0095: The Park Ranger said; “While traveling at speeds between 25-45MPH in a posted 25 MPH zone, I was finally able to catch up with LEW after more than 3 miles.” According to LEW, the Park Ranger “waited to turn on and blast his siren until he was approximately 50-100 ft behind me, just as I was entering a blind curve, frightening and startling me, drawing my attention for a split second away from the direction that I was traveling and subsequently causing me to crash into the ditch.” According to Sergio Estrada (cyclist), “He pulled up behind me fast and sirened me just like you, I almost crashed too, but I wasn’t going that fast, he just passed me and kept going. You were pretty far ahead at that point.” (photo below of the Park Ranger Pursuit vehicle)  Open this Link to Read California Department of Parks and Recreation, Vehicle Pursuit Policy 315, and Open this link to view Garrett's Video Story
  56. 5/2/2018 Wednesday, (1200hrs), Summit Road, 4.10miles North of Summit Road Origin, Blind Curve, Wrong Side, Sideswipe, CVC: 21572(a), Male (43yrs), Brian Kahn, Injuries. CHP-SWITRS  Open this Link to View Brian’s Collision Video Story
  57. 7/1/2018 Sunday (1120hrs), Summit Road, Devil’s Elbow, 3.75miles, Female (58yrs), Injury.  Diablo SP: Reference Map & CHP-SWITRS
  58. 8/11/2018 South Gate Road (SG2) Mt. Diablo SP: Reference Map
  59. 7/9/2019 Summit Road, South Gate Road (SG2) Mt. Diablo SP: Reference Map
  60. 4/8/2020 Wednesday (1200hrs), Summit Road, Devil’s Elbow, CHP Officer drove his vehicle (photo below) “in violation of section 2121650(a)VC- (crossing over double yellow lines).” Morgan Aguirre, Female (27yrs), Injury. TCR# 9390-2020-00737
  61. 5/30/2021 Sunday (1015hrs), 7392ft up (1.4miles), CVC: 21460(a) Motorist driving in the uphill lane, afraid of the road edge, Blind Curve, Gary Spinella (photo below) Male, Injury. TCR# 93202121-10249
  62. 7/3/2021             Saturday (     ) Ron Wolfe, Injury, Blind Curve passing Cyclist, Injury.
  63. 12/1/2021 Wednesday (1300hrs) (1.5miles), Blind Curve, Vehicle entirely in his lane, CVC: 21650, Rick Edmondson (photo below) (Male), Injury. TCR#9320-2021-12546
  64. 4/14/2021 (1530hrs), North Gate Road, Report# 210414N-0085 (21-321. Mount Diablo SP Collision Reports
  65. 10/12/2022 Wednesday (1014hrs), South Gate Road, (1.5miles), Blind Curve, Vehicle crossed Solid Double Yellow line, struck and seriously injured Beth (Cyclist) as she was descending (photos below)


The map below was recently provided by the Superintendent of the Diablo Range District. The Diablo SP Reference Map identifies 17 “Historic Locations of Traffic Incidents.” When we asked him to clarify what that meant, he said “Bike vs Vehicle Collisions from 2010 to 2021.”

Screen Shot 2022-09-16 at 5.46.42 AM

The Traffic Accident Data below was provided by the MDSP Superintendent in 2015.

It includes “off-road and paved.” We are interested in Bike vs Vehicles Collisions on the paved roads of Mount Diablo. NOT “off-road” mountain bike collisions. Apparently, NO other analysis has ever been done by California State Parks.

Why is the Bike Turnout Project & Bike vs Vehicle Collision Map Below Important? 

  • Because the Bike vs Vehicle Collision data resulting in serious injuries to Park Visitors was NOT used and should be the #1 priority in the State Park's screening criteria to evaluate, prioritize and determine future Bike Turnout locations.

  • Because State Parks "Siphoned Off"  $537,000 (36%) of the $1,500,000 for administration costs.

  • We submitted a Public Records Act Request #20-315 on July 5, 2022, to understand how and why the $537,00 was spent by California State Parks.

  • Because the remaining $963,000 (64%) will only fund 30 Bike Turnouts.