The U.S. Government has played an integral role in drinking water systems for many years now. The Clean Water Act, the first major legislative piece pertaining to drinking water, passed in 1974 in response to experts’ warnings of the dangerous effects of lead exposure. In 1988, the legislation was amended by the Lead Contamination Control Act, which stated drinking water system components needed to be “lead-free,” but still allowed for as much as 8 percent lead in drinking water.

More recently, there have been state-wide movements to completely restrict lead throughout the entire drinking water system. California led the way, followed up shortly thereafter by Vermont.

Reduction of Lead in Drinking Water Act

Late last year, Congress decided to make a more drastic change to reduce the amounts of lead in drinking water systems. This proposal required the percentage of lead should be less than 0.25 percent. On January 4, 2011, President Obama signed the amendment into effect. It will take three years before the provisions of the Drinking Water Act are officially enforced. When that time comes, municipalities cannot install any equipment that exceeds the lead limits set by the new law.

Now, some pump and turbine manufacturers are scrambling to construct equipment to meet these new requirements. Bronze, the most commonly used metal in the systems, contains traces of lead that exceed the new law; however, the manufacturers have devised a way to manipulate them to meet the mandates. By removing all of the traces of lead in bronze and replacing them with alloys, like aluminum, zinc or tin, manufacturers are able to make their equipment reach sub 0.25-percent levels.

One major flaw exists with this process: The “new” bronze is highly susceptible to the damaging effects of necessary chemicals added to drinking water systems. The most noteworthy harmful chemical is chlorine, which kills and prevents bacteria from spreading. While chlorine is not inherently dangerous to people, at least not in the amounts that are found in drinking water, it wears away the replacement alloys at a quicker rate than unaltered bronze. This translates into a much shorter lifespan of bronze pumps.

Advantages of stainless steel

Due to these issues with reduced pump life, manufacturers turned to different metals to construct their pumps. The most prominent choice is stainless steel. Stainless steel is proving to be better than bronze for several reasons.

First, stainless steel contains no traces of lead. So it already exceeds the limits set by the new legislation. Second, stainless steel is impervious to the negative effects of chlorine. Pumps will last longer and perform better because the chemical will not deteriorate the metal as quickly as it does with bronze. Lastly, stainless steel will handle more abrasion than bronze, so it can last longer under rigorous conditions.

While stainless steel proves to be a better alternative than its counterparts, some manufacturers use sand castings to mold their pumps. They use these castings because it is more cost-effective for them to have just one pattern to mold both stainless steel and bronze pumps. However, molding a pump with this casting will cause the pump’s performance to suffer. In order to achieve optimal pump performance with stainless steel pumps, they need to be lost wax investment castings.

Vesconite bearings

In addition to using the proper castings, bearings can have a dramatic influence on the life and performance of a pump. A relatively new material called vesconite is providing superior performance in pumps. Mostly produced from South Africa, vesconite is a thermoplastic compound with internally lubricated polymers. It has a lower coefficient of friction so the pump can operate at lower horsepower than alternative bearing materials. Moreover, vesconite contains no lead and does not succumb to chlorine’s harsh attributes.

While some of these materials and products are just now appearing in municipalities, one thing is certain: All of a pump’s benefits, whether they are a byproduct of government regulations or not, will ensure they have a longer lifespan.

Brian Daschner has been involved with the pump industry for more than 40 years. In 1998, he founded Hydroflo Pumps Inc. and has since served as the president and CEO of the pump manufacturing company. Headquartered in Fairview, Tenn., Hydroflo currently has four other facilities across the United States. Additionally, Brian is a member of the National Ground Water Association and the Water Environment Federation.

He can be reached at 615-799-9662 or bdhydroflopumps@yahoo.com.