Nice and soft: these are the qualities analyst Camille Cegnar of United Water used to describe Boise’s drinking water.

“Nice” and “soft” are often used in conjunction to describe things like marshmallows and stuffed animals…but water?

“We’re really, really lucky here in Boise because the water is truly from the nearby mountains, lakes and reservoirs,” Cegnar said.

Boise, including Boise State, is part of the United Water Idaho (UWID) public water system.

This system is supplied drinking water by private company United Water, a subsidiary of Suez Environnement.

UWID provides drinking water to about a quarter of a million people in the Boise area and Ada and Canyon counties, according to the Environmental Protection Agency (EPA).

It is the largest public water system in the state of Idaho.

According to United Water’s Annual Water Quality Report 2013, approximately 70 percent of the drinking water provided to UWID is groundwater from about 90 wells in the area.

The other 30 percent comes from surface water: namely, the Boise River.

Water from the Boise River is treated at one of two treatment plants to remove particulate matter and for pH adjustment to reduce corrosiveness.

All drinking water is treated with a small amount of chlorine, which acts as a disinfectant to kill off hazardous microorganisms and prevents diseases including cholera, hepatitis A and tuberculosis.

“We maintain a certain water quality residual to ensure adequate protection,” Cegnar said.

The chlorine residual in the UWID system ranges from 0.2 to 1.2 parts per million (ppm).

According to Idaho Department of Environmental Quality drinking water analyst Richard Lee, drinking water supplied by United Water is government regulated for quality assurance.

“The EPA outlines very specific standards for drinking water quality. It requires sampling and testing to ensure private companies follow the laws,” Lee said.

The EPA regulates over 80 contaminants from a variety of natural and human sources including microbial contaminants, radioactive material, organic and inorganic materials, pesticides and herbicides.

Water quality regulations are designed to balance the cost-effectiveness of treating the water to remove contaminants with the known health risks posed by the presence of contaminants in drinking water.

For seven years in a row, UWID has complied with all state and federal water quality standards.

The threat posed by different contaminants varies greatly from one water source to the next.

“In some parts of the valley, arsenic is also an issue. In other parts, uranium is an issue,” Lee said.

High concentrations of arsenic can cause cancer.

In its annual report, UWID reported a range of zero to seven parts per billion (ppb) arsenic in drinking water samples.

No samples exceeded the EPA limit of 10 ppb.

Uranium is also highly hazardous to human health. UWID reported uranium levels ranging from zero to 24 ppb in its annual report, with no samples exceeding the EPA limit of 30 ppb.

According to Lee, two of the largest water quality concerns across the country are nitrates and bacterial contaminants.

Nitrate levels can fluctuate due to rainfall and agricultural activity.

Nitrate contamination is a serious health risk for infants and can cause blue baby syndrome.

Cryptosporidium, a parasite from the intestines of humans and animals found in surface water, can cause an intestinal disease called Cryptosporidiosis.

According to United Water, a small amount of Cryptosporidium is present in the Boise River but has not been detected in the treated water delivered to taps in the UWID system.