Folsom watering rules and how to program around them

Folsom assigns outdoor irrigation days by street address, and which days you get depends on the water conservation stage the city is currently in. Under the Stage 2 rules the city has published, odd-numbered addresses irrigate Tuesday and Saturday, even-numbered addresses irrigate Wednesday and Sunday, and nobody irrigates Monday, Thursday, or Friday. Drip irrigation is handled separately from sprinkler irrigation. The stage moves with conditions, so the city water conservation page is where to confirm what applies this month rather than working from what you remember from last year.

Most people react to a two-day schedule by doubling the run times, which is the one adjustment that reliably makes things worse. Applying twice as much water in a single pass does not put twice as much into the soil. It puts the same amount in and sends the rest down the driveway.

Why long runs fail on this ground

Soil accepts water at a fixed rate, its infiltration rate, and that rate falls as the soil wets up. Sprinklers apply water at a fixed rate too, their precipitation rate. When application exceeds infiltration, the surplus becomes runoff. On the tighter foothill soils common around Folsom, the crossover often arrives four to six minutes into a cycle, which means a fifteen minute run spends most of its life producing runoff.

Setting up cycle and soak

1. Run one station and stand outside with a timer. Note the minute at which water starts leaving the area, running onto paving, or pooling.
2. Set that station's cycle time to about a minute less than that number.
3. Set the number of repeats so total run time reaches what the zone needs, typically two or three cycles.
4. Set the soak delay between cycles to at least 45 minutes so the previous pass has moved down before the next one starts.
5. Repeat for each station. Lawn spray zones and drip zones will land on very different numbers, which is exactly why they should never share a valve.

Most controllers made in the last decade support this directly, often labelled cycle and soak or soak interval. On older controllers the same result comes from programming the same station into two or three separate start times.

Seasonal adjustment, the setting nobody uses

Plant water demand in Folsom in January is a small fraction of demand in July, but most controllers run the same programme all year unless someone changes it. The seasonal adjust or water budget percentage on the controller scales every station at once. A rough starting pattern for this climate: 100 percent in July and August, around 80 in June and September, 50 to 60 in spring and mid-autumn, and off entirely through the wettest winter weeks. Four adjustments a year, each taking under a minute, will cut annual landscape water use more than any single equipment change.

Rain shutoff and pressure

A rain sensor or a controller with a local weather feed stops the system watering through a February storm, which is both a waste and a nuisance to neighbours. It is a small item on a quote and one of the few that pays for itself quickly.

Pressure matters just as much and gets checked far less. Drip emitters are rated for a specific operating pressure, commonly around 25 to 30 psi, while household supply frequently arrives well above that. Without a pressure regulator on the drip zones, emitters push more water than they are rated for, fittings blow off under summer load, and the zone waters unevenly. A regulator and a filter belong on every drip valve.

The state ordinance, in short

California's Model Water Efficient Landscape Ordinance sets a maximum applied water allowance for qualifying projects, based on landscape area and local reference evapotranspiration. It applies to new landscapes of 500 square feet or more, and to rehabilitated landscapes over 2,500 square feet, where the project requires a permit, plan check, or design review. Where it applies, the drawing set carries a water budget calculation, a hydrozone plan, and an irrigation schedule. Where the project has no permit trigger and sits below the thresholds, it does not apply, which covers a great many ordinary residential yard renovations.