Where the stains show up tells you a lot
| Where you see it | Likely source |
|---|---|
| Exterior walls, sidewalks, driveway, fence, pool deck | Irrigation well water hitting surfaces |
| Toilets, tubs, sinks and laundry, home on a well | Iron in the well that supplies the house |
| Discolored water after the tap sits unused, city water home | Rust or sediment in household plumbing or the water heater |
| Brief brown water during utility flushing | Sediment stirred up in the mains |
Irrigation wells and the sprinkler stain problem
Some homes water their lawns from a shallow well to avoid using city water on the yard. Groundwater can carry dissolved iron that is invisible coming out of the ground but oxidizes into orange deposits once it dries on concrete or stucco. In Miami-Dade, the county's year-round landscape irrigation rules apply to any water source, private wells included: two days a week, before 10 a.m. or after 4 p.m. Less watering means fewer new stains, but it does not remove the iron.
Treatment options for the irrigation line include iron filtration or a metered additive designed to keep iron in solution. Jorge tests the well water and explains which approach fits.
City water homes: check your plumbing
NMB Water's 2025 Water Quality Report says brown or yellow water, stained fixtures or laundry, and a metallic taste can be signs of rust or iron buildup in household plumbing, often from aging pipes or sediment. It suggests having a licensed plumber check for old galvanized pipes and, if none are present, flushing the water heater and household plumbing at least twice a year. NMB's report also says its 2025 service line inventory found no lead service lines in its system.
Both NMB and WASD flush hydrants during their annual free-chlorine period, which can briefly discolor water. That clears after running the cold tap.
Wells that supply the house
If your home draws drinking water from a well, iron is one of the most common complaints. A well water system configured from the test can include oxidation and filtration for iron, often combined with sulfur treatment and softening. The Florida Department of Health also recommends testing private drinking wells for bacteria and nitrates every year.
Cleaning existing stains
Treatment stops new stains; it does not erase old ones. Rust stains on concrete and stucco usually need a cleaner made for rust. Test any product on a small area first, especially on colored pavers or pool finishes.
Book a test
Jorge can test the house tap and the irrigation water in the same visit. Call, text or WhatsApp (305) 793-5974.
https://www.citynmb.com/DocumentCenter/View/14691/2025-CCR-ENGLISH-web-version
https://www.miamidade.gov/global/water/conservation/outdoor-water-restrictions.page
https://www.floridahealth.gov/community-environmental-public-health/environmental-public-health/water-quality/drinking-water/private-wells/
Updated 2026-10-17 · Living Waters · Jorge Canela, Water Quality Specialist