Dave Frymark remembers a 1993 trip to Walgreens well. It wasn’t pleasant. He was looking for Imodium.

“They were out of it,” said Frymark, a Milwaukee native and circulation supervisor at Raynor Memorial Libraries. “The Walgreens manager said it was really strange, that a rush of people had come in looking for (Imodium). That’s when I knew something weird was going on.”

Soon, news broke. People panicked. Cryptosporidium — a parasite that grows on fecal matter and causes gastrointestinal illness in humans — had contaminated Milwaukee drinking water, sickening Frymark and an estimated 400,000 other Milwaukee area residents.

That year, the Milwaukee Metropolitan Sewerage District (MMSD) released 9 billion gallons of raw sewage into Lake Michigan — Milwaukee’s primary source of drinking water. By 1994, when MMSD opened its 20-mile underground “Deep Tunnel” wastewater storage system, the number of gallons of untreated raw sewage dumped swiftly dropped to 176 million — an amount that could fill about 11.4 million beer kegs — and has not since exceeded the 9 billion gallons dumped in 1993. But today the question still lingers in the minds of the uneasy Milwaukee residents who cautiously boiled their tap water during the 1993 scare — how much is too much?

“I’m always concerned about water quality, even though it goes through all that filtration,” Frymark said. “I mean, who shouldn’t be? Everybody has to drink water.”

Jenelle Joset, a media law instructor with a particular interest in the issue, said she neither drinks tap water nor swims in Lake Michigan.

“We need to know how much (sewage) they are dumping and what are the long term effects, not only for us as people but for the environment,” Joset said. “The people who lived through Cryptosporidium here will always wonder, ‘Is (the water) safe?’”

And for those residents, finger-pointing is easy to do. MMSD controls the release valve that dumps raw sewage into the lake when rainwater overflows Milwaukee sewers. The facility does this to prevent raw sewage backups into Milwaukee basements.

“You either have raw sewage in your basement, or you have raw sewage dumped into your lake, which is your source of drinking water,” Joset said. “Which is the lesser of the two evils? You can see (MMSD is) between a rock and a hard place.”

According to MMSD’s spokesman Bill Graffin, the amount the facility can dump per year is measured by events, not gallons. The facility is allowed 4 – 6 overflow sewage dump events every year. But MMSD is neither the sole — nor the worst — polluter of the lake, Graffin said. He told the Tribune that several other Midwestern cities like Chicago and Indianapolis all have larger annual wastewater overflows than Milwaukee.

And although MMSD dumps billions of gallons less than it did in 1993, many still debate the long-term effects.

A study conducted by the Medical College of Wisconsin from 2002-2004 aimed to determine if gastrointestinal illnesses in children increased after overflow sewage was dumped into Lake Michigan. The researchers concluded sewage release into the lake is “potentially harmful” because hospital visits increased only for those drinking Lake Michigan water after two of the largest sewage dumps during the study.

Another study published by researchers at the Children’s Hospital of Wisconsin and the Medical College of Wisconsin links heavy rainfall and an increase in gastrointestinal disease in children, identifying 17,357 hospital visits for such diseases from 2002-2007. Any rainfall four days prior was associated with an 11 percent increase in gastrointestinal disease visits, and more rainfall was linked to greater increases.

Whether or not the damage is long-term, contaminated water harms the environment as well, according to the Natural Resources Defense Council. A 2011 report published by the council includes two Wisconsin beaches — one of which is South Shore Park Beach in Milwaukee — on a list of 13 U.S. beaches with 25 percent of beach samples repeatedly exceeding the U.S. Environmental Protection Agency’s maximum bacteria limit.

But other factors can interfere with water and beach quality, too. The Great Lakes WATER Institute debunked myths that beach advisories and closings in Milwaukee are caused by sewer overflows, as well as myths that closings and advisories in Chicago are caused by Milwaukee sewage. Instead, the institute attributes this to seagull populations and stormwater runoff from roads and urban areas. And this is not just a concern for recreational use, but also for drinking water.

Frymark said after the Cryptosporidium outbreak in 1993, he bought a carbon filter for his tap water. But common household pitcher and faucet-mount filters do not necessarily address the bacteria issue, as many filter out minerals to give consumers water that tastes better but is not necessarily cleaner, according to NSF International, a nonprofit public health and safety company. Joset said she only drinks bottled water.

Milwaukee Water Works treats and filters the Lake Michigan water distributed to residents as tap water. The MWW website maintains that their filtration process destroys disease-causing bacteria like Cryptosporidium. But according to the Centers for Disease Control and Prevention, ordinary disinfection methods should — but cannot always — kill Cryptosporidium and other parasites. Even the best filtration systems cannot guarantee disease-causing bacteria will always stay out of filtered drinking water.

Still, a report from the Environmental Working Group recommends consumers drink filtered tap water, as it states most of the 173 bottled water brands tested fill labels with “vague claims of pristine source or perfect purity — but no real facts.” In 2009 and 2010, 30 of the brands tested failed to provide any information about their water treatment processes at all. Among those were popular brands like Fiji, Trader Joe’s, Evian and Nestle’s Ice Mountain.

The Environmental Working Group does, however, report that treated sewage is often still contaminated when released into the lake. A 2007 report says Phthalates, bisphenol-a and triclosan — three hormone-meddling chemicals found in common household products — were all present at low levels in the California sewage they tested, even though it was treated.

“We know (contamination is) going in, we know at least some of it is going out, and we know that’s not good,” said Bill Walker, Environmental Working Group’s West Coast president, in the report.

In addition to the chemicals detected by Environmental Working Group, overflow sewage is often contaminated with environmentally harmful toxins, bacteria and trash. These affect Lake Michigan drinking water supply, fish consumption, shellfish harvesting and recreation.

The EPA, however, notes impacts from sewage overflows are often combined with impacts from other sources of pollution. This makes it difficult to identify cause-and-effect relationships between overflow sewage releases and health or environmental issues.

Regardless of the causes, Graffin said Milwaukee residents can decrease the amount of wastewater entering the lake if they conserve water. If less water is used and in the system, sewer overflows are less of a threat, which then reduces the amount of untreated sewage MMSD has to dump into the lake.

“Anytime there’s heavy rain, try to use less water,” Graffin said. “You can cut down by some, help the lake and save some money.”

According to the MMSD website, if their 1.1 million customers used 10 gallons less water on a day with heavy rain, basement backups and sewer overflows could be reduced by 11 million gallons. Simple changes like not doing laundry when it’s raining or taking shorter showers, in the end, affect the water in which Milwaukee residents swim and drink.

“If we don’t have excess water in the system, (MMSD has) the capability to clean it and treat it before it’s dumped, which is what we want,” Joset said.

Conserving individual water use is something student organizations like Students for an Environmentally Active Campus encourage.

Claire Wild Crea, a junior in the College of Arts & Sciences and vice president of SEAC, said the organization will sponsor Earth Week April 23 to 27 to promote conservation awareness on campus.

“SEAC definitely encourages (Marquette) to conserve water, food really in every aspect,” Wild Crea said. “Conservation is the best way to positively impact the Earth … We can do small things to ensure we keep our planet healthy for everyone.”

Tyler Atkinson, a junior in the College of Arts & Sciences, also encourages Marquette to do its part. Atkinson is an intern for Project H2Oscore, a business that helps residential homeowners and small business owners understand their water usage by allowing them to track the amount used — as well as the money they save by conserving.

“Marquette has made some progress on the issue as seen with things such as the dual-flow toilets in newer buildings like Zilber Hall,” Atkinson said. “If the entire campus were to install even something as simple as faucet aerators in the restrooms, it would make a bigger difference than you think.”

But regardless of who and what pollutes water the most, Joset and Frymark agree pointing fingers isn’t the way to solve the problem.

“Everybody needs fresh water — it’s absolutely critical to life,” Frymark said. “And it’s everybody’s problem. If you use water, it’s your problem.”