Browns Valley Open Space Preserve 2025

Mar 9, 2025 (Sun)

BAOC

Browns Valley Open Space Preserve Vacaville, CA

Director: Scott Aster (415.456.8118)
Course Setter: Andrew Masalkov

Type C: Low-key local. Offers a subset of courses of the regular local event

This event will offer courses for first-timers & experienced orienteers; beginners and non-members are welcome; free beginner instruction will be available

Past events:
2024 2023

By Andrew Masalkov

Browns Valley is in full bloom, with green grass and wild flowers starting to show up on the southern sides of the hills. The ground is soft, and most of the park is already dried, making it a perfect time to enjoy the beautiful, but steep, landscape. Runnability might not be the best — there is lots of stony ground, and small rocks scattered all over the place add to the challenge. Grazing cows, which are present in the park, left a lot of small holes, so one needs to be careful while looking at scattered terrain around controls. Poison oak is there, but not very abundant — it is easily avoidable.

The Start for both the White and Score-O courses will be located about a 650-meter (0.4-mile) walk from the registration area at the local school. (The location is the same as used last year.) Follow signs to the closest park entrance: from the school, head south on Wrentham Dr, turn left onto Wethersfield Dr, then left onto Rambleton Dr; after about 30 meters, turn left onto a path to a gate.

The Start is up the hill, another 200 m walk with around 50 meters climb. The route to the Start will be marked. Plan for a 10-minute walk from the school.

The Finish is located near the entry gate. The walk back to the school will be about 450 meters (1/4 mile), reversing the route from the school to the gate.

The White course will have a (straight-line) length of around 2.1 km (little bit more than usual, but this was a tradeoff for a lower climb number); the climb will be about 40 meters; there will be 10 controls.

The Score-O will have 1- and 2-hour options using the same map. The total number of controls is 35, amounting to 410 points in total. Control values are in the range of 10, 20, and 30 per control, depending on location. There are premiums for visiting the highest park vistas — the more you sweat, the more you get. The late penalty is 5 points per minute (and fraction of a minute) late — for example, if you are late by 3 minutes and 10 seconds, then 20 points (15 for 3 minutes, 5 for 10 seconds) will be deducted from your final score. Plan accordingly.

The map used is a couple years old, and is mostly correct. The maps for both courses are printed at 1:7500 scale. Some areas require corrections, but nothing dramatic.

Note for White-course participants: 

Trails might not be distinct on the southern hillside — not enough people have used them yet, and some trails are overgrown with grass. In any case, controls are set such that they are visible from one location to another to avoid bigger confusion.

There will be some water on the Score-O course. One dedicated water drop is close to the Finish area, not associated with any control. Another two water controls will be located on the northern part of the map. There is no water on the White course.

The following is optional — you may start at any time until starts close at 12:30: per Rex's suggestion, we might try to have a mass start for the 2-hour event around 10 AM, and around 10:50 for 1-hour participants. That way we can get everyone finishing around noon, and really have a social!

Note that everyone must return to the Finish by 2:00, whether or not they have completed their course, and then return to the school to download.

Don't forget that the Daylight Saving Time change happens this Sunday.

Updated: Mar 9, 2026, 9:51 PM PDT Edit