This winter, we’ve been hearing plenty of warnings about the dangers that ice and snow pose, especially to children.

What may be surprising to many people, however is that water in its unfrozen form also represents enormous risks to children in the United States. 

Water insecurity,” shorthand for problems with the quantity, quality or reliability of water, can be found in almost every corner of the U.S., from Alaska to Florida.

National, state and nongovernmental organizations should be measuring water insecurity. A metric comparable to the Department of Agriculture’s food security scale would be a feasible way of doing so. The short food security questionnaire has transformed our understanding of the just how widespread food insecurity is, and how harmful it in all kinds of unexpected ways: more illness, poorer school performance, excessive weight gain, depression.

There is reason to believe that water insecurity may be posing the same kinds of threats.

Such a scale doesn’t yet exist, but we are not far off from having one. I am leading a consortium of scholars in developing the Household Water Insecurity Experiences Scale, a short survey that can quantify water insecurity in any low- or middle-income country.

A scale for measuring water insecurity in the U.S. would be enormously useful as we seek to understand how children and others, are impacted by dangerous water, and more importantly, how we can keep them safe.

Certainly, there is no shortage of reports of problems. In cities, there are increasing numbers of reports of lead and copper contamination in drinking water. Entire schools have had to shut off drinking water.

In rural areas, wells are contaminated with runoff from fertilizer and bacteria. Everywhere, water infrastructure is crumbling and the millions of households have had their water shut off water for non-payment.

The consequences of water insecurity for children show up in a variety of ways, starting even before birth. Contaminants in drinking water can harm the fetus. For example, tap water consumption at Camp Lejeune in Jacksonville, North Carolina was associated with fourfold risk in birth defects and child cancers.

Water is an important part of toddlers’ diets, but sadly, a nationally representative study of U.S. kids found that those who drank more tap water had higher blood lead levels. This is tragic because lead exposure in early childhood impairs intelligence and future earning potential. When caregivers are unsure of the safety of tap water, they tend to feed toddlers sugary drinks, which contributes to both cavities and obesity, perhaps some of the more unexpected consequences of water insecurity.

Older children, including the roughly two million homeless children here in the U.S., suffer from water insecurity, too. They can experience stigma, anxiety over paying the water bill, and stress as they figure out how to keep their bodies and clothes clean (particularly trying during menstruation). Teens can also bear the extra work that cooking without running water requires.

Migrant children may bear a special burden. Jakelin Caal Maquin, the seven-year-old Guatemalan girl who died while in custody of the U.S. Customs and Border Patrol, was allegedly not given water for eight hours. Individuals in Flint were denied water and filters if they could not provide identification.

These anecdotes suggest that water insecurity in the United States is very real, but currently, we don’t have good data on its prevalence among any population here.

This allows the problem, and its consequences, to remain hidden.