Ultra Running Hub Castro Valley, CA, United States · Saturday, April 24, 2027
SPASM Lake Chabot 50 km
Calculated from 50 km alone — the organiser has not published an elevation profile. Read 2.5 as a floor, not a verdict.
What the course asks
DUV results for the 2026 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.
Typical conditions, April
Regional 2001-2020 average for April — NASA POWER, grid elevation 233 m. Not a forecast.
Results history
| Year | Race | Finishers | Men's winner | Women's winner |
|---|---|---|---|---|
| 2026 | 50km | 20 | Adam Wolf · 04:25:29 | Dora Jih · 05:43:34 |
| 2025 | 50km | 23 | Marc Solkov · 03:55:34 | Nami Kato · 05:38:23 |
| 2024 | 50km | 16 | Jeffrey Clark · 04:35:31 | Flora Eppler · 06:55:42 |
| 2022 | 50km | 19 | James Scanlan · 04:06:11 | Beverley Anderson-Abbs · 04:37:00 |
| 2019 | 50km | 18 | Adelaido Solis · 04:16:02 | Beverley Anderson-Abbs · 04:23:12 |
| 2018 | 50km | 35 | Guillaume Hansel · 04:05:17 | Thia Angelo · 04:21:21 |
| 2017 | 50km | 25 | Tim Larsen · 05:17:25 | Sherry Lee · 05:59:02 |
| 2016 | 50km | 26 | Alejandro Rodriguez · 04:52:56 | Rosalina Monrox · 06:19:57 |
| 2015 | 50km | 20 | Fabio Rizzo Cascio · 04:18:25 | Beverley Anderson-Abbs · 04:28:49 |
| 2014 | 50km | 28 | Ronald Hess · 04:14:47 | Sophia Shi · 05:12:08 |
The field shrank 13% between 2025 (23) and 2026 (20). 25% of the 2026 field were women.
DUV results for the 2026 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.
Course notes
- gear With trail terrain, choose a shoe with moderate cushioning for optimal performance.
Gear for this race
Chosen for 50 km of trail.
- Trail Running Shoes 50 km of trail — cushioning that is still there in the last quarter.
- Race Nutrition 50 km of self-supported fuelling between aid stations.
- Hydration Vests Flask capacity for 50 km, without the bounce.
- GPS Watches Battery life first — a 50 km day outlasts most full-GPS modes.
Overview
Organised by Coastal Trail Runs, the SPASM Lake Chabot 50 km takes place in Castro Valley, CA, sending runners from the Marina around the Lake Chabot Reservoir and into the surrounding hills.
The 8-hour time limit is tighter than 84% of 50k cut-offs and more generous than 16%, requiring runners to sustain a minimum pace of 9.6 minutes per kilometer to finish before the clock runs out.
With 20 finishers in 2026, the event features a quiet trail environment—smaller than 67% of 50k fields and bigger than 31%—leaving plenty of open space along the route.
Similar races
Other 50K trail ultras, closest in distance first.