SAGINAW, MI -- Municipal water treatment systems typically only get attention when the system breaks down, like in did in Flint.

In nearby Saginaw, though, officials assure the more than 170,000 people in the region who receive water from the Saginaw Water Treatment Plant that they have no cause for concern.

"We just want our customers to be assured that their water is safe to drink," Saginaw Director of Water and Waste Water Kim Mason said.

Full coverage: Flint water crisis

Mason explained that Saginaw has a long history of providing city residents and the water system's many wholesale customers very high-quality water.

"We're meeting all federal and state drinking water standards," she said. "We're meeting or exceeding those standards."

It's not just Saginaw city residents who receive water treated at the city plant. Through the city's wholesale contracts, the plant provides water to 19 other cities, townships, villages and authorities spread throughout the region.

If you live in any of the following areas, you probably have Saginaw water coming from your tap:

Albee Township, Village of Birch Run, Birch Run Township, Blumfield Reese Water Authority, Bridgeport Township, Buena Vista Township, Carrollton Township, Frankenlust Township, James Township, Kochville Township, Saginaw Township, City of Saginaw, Village of St. Charles, Spaulding Township, Swan Creek Township, Taymouth Township, Thomas Township, Tittabawassee Township and the City of Zilwaukee.

Details about how Saginaw's water system is meeting state and federal standards can be found in annual water quality reports published by the Saginaw Water Department.

By and large, the reports show levels well within state and federal water quality and safety.

A handful of issues have been identified over the last several years, including some cases where elevated lead levels were identified, though there have been no violations of state standards in recent years.

Database of Michigan public water system lead levels

Mason started working at the city's water treatment plant in 1993 and served as the treatment plant superintendent before being named director in 2010.

"Since I've been in management there, I don't recall us being in violation of any state or federal drinking water parameters," she said.

An aging infrastructure

The 87-year-old plant, which went into service in 1929, initially treated water from the Saginaw River.

But staff at the plant and city resident alike are happy that is no longer the case.

In 1946, Saginaw and Midland partnered to form the Saginaw Midland Municipal Water Supply Corp. and built pipes to carry water 65 miles south from a new Lake Huron intake facility at Whitestone Point, near Au Gres.

City's website: Where does my water come from?

Since 1948, it has been the sole source of raw water for both communities. Most of Bay County now gets water from the intake as well.

Though the plant is capable of pumping out up to 105 million gallons of treated water each day, it can only treat up to 52 million gallons of water. The typical daily flow is much lower, closer to 17-18 million gallons.

Mason explained that Lake Huron is a much better water source than the Saginaw River, both because of the large volume of fresh water available and because conditions impacting water in the lake are much more predictable.

"We're less prone to having large changes in water quality due to excess rains or large storm events," she said. "It makes our job easier to provide effective treatment."

Despite having a very good source, Mason said there are still challenges in the effort to provide high-quality drinking water to the region.

Saginaw's aging water distribution network includes some pipes made of substances like lead, which is no longer used because of the health implications. Those older lines are replaced whenever the city completes a construction project or when repairs are being made, but Mason said it will take a long time to eliminate that problem entirely.

"We estimate that maybe 25 percent of the system would have those types of lines in them," she said.

Testing water for lead and copper is required every three years. Those tests were conducted in 2007, 2010 and 2013, and will be conducted again in 2016.

Over that time, five sites have reported tests for lead showing levels exceeding the 15 parts per billion "action level" for the contaminant.

2007: 1 site in the City of Saginaw

2010: 3 sites in Carrollton Township, Frankenlust Township and the City of Saginaw

2013: 1 site in Bridgeport Township

But none of those tests resulted in a violation of the standards.

That's because compliance with lead and copper standards is based on the 90th percentile, where nine out of 10 samples must be below the "action level." Since only a single test came back higher than the standard in each of the above cases, no violation was issued.

Treatment efforts

In addition to incrementally replacing the older pipes, Saginaw also takes action at the treatment end to minimize corrosion of the lines and, hopefully, keep the lead content well below safe levels.

Part of that effort, Mason said, is to maintain certain pH and alkalinity levels to ensure it does not corrode the pipes.

It also includes the introduction of calcium oxide, known commonly as quicklime, which becomes calcium hydroxide after being mixed into the water. The compound coats pipes in the water treatment system, further protecting them against corrosion.

The about 30 employees who work at the Saginaw Water Treatment Plant conduct tests each day and make adjustments all aimed at keeping clean, high-quality water flowing.

See for yourself all the information contained in Saginaw's annual Water Quality Reports:

* 2014 Saginaw Water Quality Report

* 2013 Saginaw Water Quality Report

* 2012 Saginaw Water Quality Report

* 2011 Saginaw Water Quality Report

* 2010 Saginaw Water Quality Report

* 2009 Saginaw Water Quality Report

The reports above show data on how Saginaw's water system has met standards for chlorine, flouride, barium, combined radium, turbidity, coliform bacteria, lead, copper, trihalomethanes and halocetic acids.

It also includes numbers on other substances that are not regulated at the state or federal level, like sodium, bromochloroacetic acid, chromium, hexavalent chromium, molybdenum, stronium and chlorate.

Lead levels

Though no Saginaw-area communities were found in violation of lead standards over the last several years, testing has showed a few communities have seen average lead levels that begin to approach the 15 parts per billion (ppb) threshold:

2007

City of Saginaw: 6 ppb

Village of Birch Run: 5 ppb

2010

City of Saginaw: 11 ppb

Frankenlust Township: 10.5 ppb

Carrollton Township: 10 ppb

2013

City of Saginaw: 8 ppb

Spaulding Township: 6.5 ppb

Birch Run Township: 6.5 ppb

Lead is not the only issue of concern when it comes to the area's drinking water.

In 2013, Buena Vista Township received a violation because the total trihalomethanes in the community's drinking water exceeded the state standard of 80 parts per billion in the third quarter of the year.

The problem with trihalomethanes, a byproduct of the disinfection process that has been linked to cancer and birth defects, has not gone away for Buena Vista Township.

The township notified residents in January that tests again showed trihalomethanes exceeding the standard in 2015.

Related: Buena Vista residents notified of contamination in drinking water

Township officials report that testing conducted in January shows that efforts to correct the situation have successfully reduced the trihalomethane rate below the threshold of 80 parts per billion.

Testing results from 2015 is currently being compiled from all 19 communities for the latest system-wide water quality report, published on the city's website each spring.

Mason said she does not expect any issues like Buena Vista Township's elsewhere in the system when that data is released.

"I don't believe any other communities will have any notifications or any issues with the regulations," Mason said.

A popular slogan in the 1940s, when Saginaw and Midland completed their project to bring Lake Huron water south, bragged that Saginaw provided residents with "the best water in the world."

Mason said she still has documents in her office that state the city's water treatment service has been "providing the world's best water since 1946."

She was not ready to make quite such a claim in 2016, but Mason is still very proud of the quality of the water provided to residents in the region.

The key to maintaining that quality despite the challenges, she said, has been the department's highly qualified and hard-working staff.

"We have very dedicated and well-trained staff," Mason said. "We have certified operators, many of whom have been in this field for quite some time."

Mark Tower covers local government for MLive/The Saginaw News. Contact him at 989-284-4807, by email at mtower@mlive.com or follow him on Twitter, Facebook or Google+.