THE 110° DESERT COOLER
A solar, gravity-fed build for chickens and French bulldogs in Borrego Springs
Dawn Littlefield · The Ark Initiative · October 9, 2026 · Ark Unit 1 build guide
For 110° in Borrego Springs, California, you don't fight the heat with AC. You use what already works here: shade plus dry air plus gravity water. This is a solar, gravity-fed build for our coop and Frenchie yard that runs off the same logic as the Ark water system.
The core logic
Borrego at 110° sits at 10 to 15 percent humidity, which is perfect for evaporative cooling. You don't need to cool the air. You need to cool surfaces and create a 15 to 20 degree microclimate they can move in and out of.
1. The Coop Cooler: wet wall plus chimney
Think chicken desert cooler, not mister.
North side wet pad. Build a 4x4 ft frame with burlap or swamp cooler pad. Above it mount a 30 to 50 gallon gravity header tank. A slow drip valve wets the pad all day. No pump needed during cooling hours.
Solar exhaust on the south roof. A small 12V solar fan (about $25) on the peak pulls air through the wet pad and across the roost. Sun means more heat means more fan speed. Automatic.
Deep shade plus earth. Double shade cloth, 80 percent over the run, 60 percent over the pad so it doesn't dry instantly. Keep the floor as 4 to 6 inches of damp sand under shade. Chickens cool through their feet.
No mist inside the coop. At 103° and up, wet litter means ammonia plus respiratory issues. Cool the air coming in, not the birds directly.
Target: 110° outside, 85 to 88° inside the coop with airflow.
2. The Frenchie Yard: cool station, not whole yard
Frenchies can't do evaporative vests alone at 110°. Those vests heat up in 20 minutes here. They need a place to self-regulate.
Cool slab plus shade cave. Pour or place 2x2 ft paver stones in deep shade, under your shade sail. Run a buried drip line under the pavers in the morning for 5 minutes. The thermal mass stays 75 to 80° all day. This is their go-to.
Mister ring on a timer, NOT over the slab. Mount a low-pressure mister line on the perimeter of the shade structure, 7 feet high. On a gravity timer: 15 seconds on, 10 minutes off, from 11am to 6pm. It drops the surrounding air 20°, but their bed stays dry. Wet Frenchies in direct sun equals hot skin.
Water station. Low, heavy ceramic bowl in shade, refreshed from your header tank with a float valve. Add a second bowl with a splash of electrolytes on extreme days. No deep buckets, brachycephalic risk.
3. How it ties to our water system
This is the same system we already posted about previously.
Header tank. One 55-gallon drum on a 6-foot stand (coop roof height). Fill it once in the morning via solar pump from your main storage. All day it gravity-feeds the wet pad, the Frenchie misters, and the paver drip.
Solar pump. 12V 100W panel to a 12V Shurflo pump. Fills the header tank by 10am, then shuts off. Zero grid.
Filter. Simple sediment filter before the drip valves. Borrego dust clogs misters fast.
Shopping list for Borrego
55-gallon drum plus stand, float valve, 1/4 inch drip tubing plus adjustable drip emitters. Aspen swamp pad or burlap roll 4x8. 12V solar attic fan plus 100W panel plus small battery. 80 percent shade cloth 10x12, mister kit with 0.3mm nozzles. Two pavers, ceramic water bowls. Timer: gravity battery timer like Galcon 7001.
Your 110° day routine
7am. Fill header tank. Hose down sand in chicken run.
10am to 6pm. System runs itself. Check pad is damp, not dry or streaming.
Check twice. Frenchies out for max 10 minutes at a time over 100°, then back to cool slab inside. Chickens: if panting with wings out, add frozen water bottle to coop behind fan.
6pm. Shut misters off to let everything dry overnight. Prevents bumblefoot and hot spots.
For your flock
No corn or scratch after 10am on 110° days. Digestion raises body temp. Watermelon plus cool water instead.
Built and tested at Ark Unit 1, Borrego Springs, California.