Zim Zim Spring

Napa County, California · Near Angwin
38.7550°N, 122.2850°W · 902 ft
70°F 70°F air · Good soaking weather 902 ft Open Short Walk SFW Camping nearby (13.7 mi)
Aerial view of the ground around Zim Zim Spring LiDAR bare-earth view of the same ground around Zim Zim Spring
Aerial LiDAR bare earth

Drag the handle to compare the two views. The orange dot marks the spring, in a frame about three quarters of a mile wide.

Zim Zim Spring is a named warm spring in the Knoxville Wildlife Area of Napa County, about fifteen miles from Angwin. State conservation land, open to visitors. Its water is logged at 70 degrees, which is a long way short of bath heat. The name is the most memorable thing about it and nothing on file explains it.

Location

Knoxville Road runs a tenth of a mile away; the record calls the approach a short walk. Under a thousand feet, the spring sits in the state wildlife area, where winter brings about twenty inches of rain and snow is a dusting at most. The Oak Shores day use site, nearly fourteen miles away, is the only campground listed.

Midwinter carries the best-months tag on file. Check the wildlife area's current rules before you go, since state conservation land can carry seasonal restrictions. Open access, no fee recorded. Water this cool is for wading at most, and nothing on file says there is anything to wade in.

Terrain

Aircraft with laser scanners measured this ground to within inches. The scan strips out trees and buildings, leaving the bare shape of the land around Zim Zim Spring.

Setting
Hillside
The spring sits on a steep slope that climbs to the north.
Highest ground nearby
349 ft above the spring
Within a quarter mile, to the north
Cross-section through the spring

A slice through the ground from north to south, about 0.6 miles end to end.

Elevation data: USGS 3D Elevation Program. Aerial imagery: USGS The National Map. Public domain.

Heat Below
144 milliwatts per square meter of heat flow

That's about twice the US average of 65. It's higher than at 91% of the springs on this site.

Heat flow measures the warmth working its way up through the ground from deep inside the earth. Where it runs high, rain and snowmelt that seep down through cracks in the rock come back up hot.

Heat flow estimate: Stanford Thermal Earth Model (Aljubran & Horne, 2024), CC BY 4.0.

Monthly Climate
48°
Jan
50°
Feb
53°
Mar
59°
Apr
65°
May
75°
Jun
79°
Jul
78°
Aug
74°
Sep
66°
Oct
54°
Nov
48°
Dec
Annual Precip: 20.9 in Annual Snow: 0.6 in
Best Time to Visit
January Air 48°F · Water 70°F · +22° contrast
December Air 48°F · Water 70°F · +22° contrast
February Air 50°F · Water 70°F · +20° contrast
January offers 31°F more contrast than July
Current Conditions
70°F
ESE 3.6 mph 36% Good soaking weather
Today 87° Low 52° Sunny
Wednesday 79° Low 53° Sunny 1% precip
Thursday 81° Low 56° Sunny
Friday 89° Low 58° Sunny
Saturday 89° Low 57° Sunny
Nearby Camping
Nearby Camping
Oak Shores Day Use Area (Ca) 13.7 mi away

Overview Nestled between Blue Ridge and Cedar Roughs east of Napa Valley, Lake Berryessa provides ample public recreation opportunities. Popular activities on and around the large, yet uncrowded lake include fishing, boating, water skiing, wake boarding, jet skiing, sailing, swimming, kayaking, canoeing, wildlife viewing, hiking, biking and picnicking. The Dufer Point Visitor Center offers year-round interpretive events and exhibits highlighting natural and cultural resources. Lake Berrye...

Reservable Yes
Reserve on Recreation.gov →
Temperature
70°F
Warm Hot Boiling
Water Temp 70°F (21°C)
Avg Air Temp 62°F
Above Ambient +8°F
Mild soaking conditions September
Access
Open
Road Access Short Walk
Nearest Road Knoxville Road
Distance to Road 0.1 mi
Land
Ownership State
Agency SFW
Designation State Conservation Area
Unit Knoxville Wildlife Area
Manager SFW
Protection 2 - Permanent protection, some use allowed
Frequently Asked Questions
What is the water temperature at Zim Zim Spring?
Zim Zim Spring has a water temperature of 70°F (21°C). This is a warm thermal spring.
Where is Zim Zim Spring located?
Zim Zim Spring is located in Napa County, California at 902 feet elevation, near Angwin. Coordinates: 38.7550°N, 122.2850°W.
How do I get to Zim Zim Spring?
Zim Zim Spring has Short Walk road access, with the nearest road being Knoxville Road (0.1 mi from the road).
Is Zim Zim Spring free to visit?
Zim Zim Spring has Open access. It is managed by SFW.
Can I camp near Zim Zim Spring?
Yes, Oak Shores Day Use Area (Ca) is located nearby (13.7 miles away).