In theory, because water is hard to come by in the arid West, it should be well taken care of.

But the West sometimes squanders its limited water. We have contaminated creeks, polluted rivers, broken bays, fouled beaches and, even today, hundreds of thousands of people across California who lack reliably safe drinking water.

This week, the Diego County Water Authority disclosed a problem close to home: The region’s main water supplier was cited for failing to properly operate one of the region’s major drinking water treatment plants.

State regulators said it’s “likely” that the problem didn’t create a public health threat and that the Water Authority’s water eventually met state safety standards before it left the plant and actually got into our homes.

The citation is a rare one for a major water agency and is officially classified as a violation of “treatment technique.”

The largest agencies tend to be well-funded and closely watched. The Water Authority hadn’t been cited for such a violation since at least 1995, if ever.

But there have been dozens of other water-quality citations issued to over 100 different San Diego water providers in the past five years, according to state and county regulatory records. Most violations were issued to small districts, which can have a harder time maintaining and upgrading equipment.

That’s partly why the Water Authority’s recent violation was a bit rattling. The Water Authority imports water into San Diego from Northern California and the Colorado River and then sells that water to cities and local water agencies across the county – including the city of San Diego – which are known as member agencies. Not all of its water passes through the same treatment plant, though.

“In general, the [Water Authority] and member agencies are very well run utilities and have very few if any violations,” Sean Sterchi, the top state drinking water regulator for the San Diego region, said in an email. “The small water systems on the other hand often have monitoring and reporting violations and some of them are out of compliance with water quality standards, e.g. uranium in the back country where they have fractured rock wells, or secondary standards, e.g. iron and manganese.”

The only other drinking water violation issued so far this year in San Diego proves the point: It was the Pine Hills Mutual Water Company, which serves typically pristine mountain water to about 235 customers near Julian. (“Company” is a term used by smaller water agencies that are formed by groups of local residents – they are, in reality, nonprofits.)

The Pine Hills violation drew a “Tier 2” citation like the Water Authority’s, which means the problem did not cause a public health emergency and the public wasn’t told immediately.

The water coming out of one of the nonprofit mutual company’s groundwater wells was cloudy. The cloudiness, in and of itself, isn’t a problem, but it can interfere with disinfection and allow pathogens to grow.

Ken Waite, the president of the Pine Hills board, said the issue was only cosmetic and tests didn’t show a public health risk from the water.

“It was strictly an appearance issue,” he said.

Pine Hills Mutual Water Company, which has an annual budget of $189,000 and one full-time and two part-time staffers, was fined $500. The mutual took the problem well out of service.

The modern era of water-quality regulations began about 50 years ago.

A burning river in Ohio led to the Clean Water Act in 1972, and trace carcinogens water supplies back east and a waterborne-salmonella outbreak in Riverside helped prompt the Safe Drinking Water Act two years later. Tap water also remains more highly regulated – not to mention cheaper – than bottled water.

Still, small water districts have struggled to maintain treatment facilities, keep staff and do all the required monitoring. This year, Gov. Gavin Newsom’s budget includes over $100 million to help ensure more Californians, especially those in rural areas, have safe drinking water.

In San Diego, there over 200 water providers.

Of those, about half have had no drinking water violations in the past five years.

Most of the rest only had a handful of violations – 50 water providers had fewer than three violations.

But some had a lot of violations, a sign of the small districts’ struggle to pay for the treatment infrastructure needed to comply with water quality regulations.

Mike Workman, a spokesman for the county, said most of the violations county regulators find are related to aging infrastructure that is vulnerable to leaks or contamination, as well as water providers who don’t do all the testing they are supposed to do.

The most serious violations involve bacteria and elevated nitrate levels. For high bacteria levels, residents are immediately told to boil their water. For high nitrate levels, consumers are directed to use another water supply.

The state Division of Drinking Water handles the bigger agencies, but San Diego County’s department of environmental health inspects the smallest water systems with less than a few hundred customers. Those 132 small agencies includes the Pine Valley Bible Conference Center and Shady Oaks Trailer Ranch in Boulevard, which were both cited last year for improperly monitoring for bacteria. That doesn’t mean bacteria was found, it means it wasn’t properly looked for.

One district, the Pauma Valley Mutual Water Company, has been cited for 25 violations since 2015, mostly because it struggled to control levels of nitrates, a chemical that can occur naturally or because of contamination from fertilizer and animal or human waste.

Not many people were affected, though, according to a 2017 citation: The mutual water company serves 120 people – 25 homes, a seven-unit apartment complex and a restaurant. It also sought state help to get the problems under control.

Likewise, Guatay Mutual Benefit Corporation, which serves 100 people in a tiny East County town has been issued 18 violations, many for high levels of uranium.

The big-districts-are-OK rule of thumb doesn’t always apply.

For instance, Camp Pendleton has repeatedly found unacceptable levels of bacteria in water supplies for 39,000 Marines and other base personnel.

Some of the violations have little chance of putting anyone at risk. Six times since 2011, the city of San Diego failed to properly monitor for nitrates coming out of a well near El Cajon. Only a tiny amount of water comes from there and it’s treated before anyone drinks it.