Nitrate in water usually comes from fertilizer, septic systems, and animal waste. It can spike after heavy rain. It is a particular concern for very young infants.
In Florida, Nitrate was reported by 839 community water systems serving about 16,948,478 people. 1 of those readings were above the federal legal limit, together serving 148 people. It was measured by 1,559 systems in all, so it was detected in 54% of the systems that tested for it.
The highest reading relative to the limit was at Ranch Oaks Estates in Hillsborough County, at 150% of it.
Where it comes from: Runoff from fertilizer; leaching from septic tanks and sewage; erosion of natural deposits.
Enforceable. A utility must stay at or under this.
Health-based, not enforceable. Often lower than the limit, sometimes zero.
California has not published a PHG for this substance.
Health effects the EPA associates with it: Serious illness in infants under six months (blue-baby syndrome) if untreated.
Water at or under the legal limit meets federal safety standards. A reading above a health goal is not the same as being unsafe, and health goals are set purely on health without regard to cost or treatability. Both are shown so the margin is visible either way.
Showing the 25 highest of 839 systems that reported Nitrate.
These figures describe water as delivered by each utility, not what your home’s plumbing adds after it arrives. Informational; not a substitute for testing your own tap.