Your curls look duller, frizzier or flatter than they did, and you are using the same products you always used. Maybe you moved, or your building changed its water. Water is the one part of the routine you cannot see, so it is the first suspect. Before you change anything, it helps to know what hardness can explain and what it cannot.
Start with the number, not a symptom
Water hardness is mainly a measure of calcium and magnesium, commonly reported as milligrams per litre of calcium carbonate. The USGS calls 0 to 60 mg/L soft, 61 to 120 moderately hard, 121 to 180 hard, and anything above 180 very hard. Those bands describe the water. They do not diagnose your hair or your scalp.
A city page is useful because it gives you a documented starting point. It is not a reading from your shower. Source mix, neighbourhood, season, a building softener and private treatment can all change what reaches a particular address. That is why Rizzado keeps the original utility source next to every number.
Curious how a routine is built from numbers like these? See how Rizzado works, step by step.
See how Rizzado worksWhat laboratory studies actually show
Laboratory work has shown that human hair can take up calcium and magnesium from water. In that work, the condition of the fibre mattered more than the water category: oxidatively damaged or bleached hair took up more. That supports a careful statement about mineral exposure. It does not prove that hard water makes every curl dull, dry or weak.
Mechanical results are mixed. One small experiment found no statistically significant difference in fibre strength or elasticity after exposure to hard water. Other experiments, under different and more extreme conditions, found lower fibre strength. The studies do not establish a universal result for curly hair in everyday routines.
Use the result as a controlled question
If your routine changed at the same time as your water source, treat the water as one possible factor. Keep your wash method, styling and climate context visible. Then make one change at a time and compare several wash days, rather than reacting to a single difficult day.
Sudden shedding, itching, flaking or scalp pain are not evidence of mineral buildup. Those signs deserve clinical attention when they persist. A hardness number cannot establish the cause of a scalp condition.
What this means for your routine
Treat hardness as one question to check, not as an answer. If your utility publishes a figure for your address, write it down with the year and the report name. Then compare your last several wash days before and after the change you noticed.
If the same products suddenly behave differently, make one controlled change at a time, such as a single clarifying wash, and keep everything else the same. If scalp pain, itching, flaking or sudden shedding persist, see a clinician before you try another product.
CITY DATA
Compare a published local source
These pages keep the utility or public authority source next to the figure. They are a starting point for a question, not proof of what is happening to your hair.
Browse every city with a primary source