Water is a precious resource. Many parts of the world are facing water use limitations due to drought, polluted ground water, or deteriorating water tanks, mains and lines that cause the loss or contamination of potable water.  Water is critical to human health, agriculture, industry and safety (i.e. fire fighting).

Stainless steels have been used in the treatment, storage and distribution of drinking water for over forty-five years.  While stainless steel plays an important role in water treatment plants and desalination, this article will focus specifically on water conservation, distribution and building applications and the contribution of stainless steel to the sustainability and resiliency of these systems. The resource section at the end of this article provides papers, articles and brochures for further reading.

Building Applications

Stainless steel is increasingly being used for small on-site water storage, treatment or filtration units. These small units clean building waste and gray water, so that potable water consumption is reduced. They are ideally combined with stainless steel roofs and drainage systems, which unlike many other roofing materials, have metal run-off levels well below drinking water limits, making them an ideal solution for potable, irrigation or gray water applications. Capturing and using rainwater minimizes the structure’s overall environmental impact.

Water Storage & Transportation

Stainless steel is increasingly being used to store and transport potable water to minimize loss to the environment because it combines excellent seismic and corrosion performance. Extensive comparative global research on metal corrosion using a wide range of soils and water types has consistently demonstrated the superior performance of stainless steel, even in aggressive, high-chloride content soils. However, it is critical to select an appropriate alloy for the environmental and water conditions based on expert guidance.

Water Tanks
When a water storage system is breached due to a screen failure, steel tank corrosion perforation, a knot hole in a wooden tank, or deteriorating concrete, the effect on human health can be significant. These problems can be avoided by using tanks made from appropriate stainless steel alloys. Additionally, relining deteriorating concrete water tanks with stainless steel has been found to be a cost-effective solution for preventing water loss.

Water Mains
Leakage of drinking water is a major challenge in all parts of the world. The Organisation for Economic Co-operation and Development (OECD) concluded that water loss in major cities can exceed 40%. Loss of treated, potable water into the environment from leaking pipes is an expensive and unsustainable waste of one of the world’s most important natural resources.

Additionally, the contamination of water from both pipe corrosion and infiltration of toxins and bacteria from the surrounding soil presents both environmental and human health concerns. To solve these problems. stainless steel water lines and liners for existing crumbling concrete pipes have been used in Asia and Europe.

Water Main Connecting Lines
The water lines connecting water mains to individual buildings are called service water lines and were historically made from lead and other materials that can leach compounds and are deteriorating over time, resulting in both significant water loss and public health concerns. In fact, 95 % of all leak repairs are typically in these small diameter pipes and, because the leaks are relatively slow, they can go unnoticed for years.

In Japan, Taiwan and Korea, there has been widespread replacement of these lines with partially corrugated stainless steel tubing. Stainless steel pipes have helped to significantly decrease water losses. Pipes made of stainless steel have a higher strength to weight ratio, are easier to work with, are resistant to corrosion and are strong enough to withstand shocks from seismic activities.

The partially corrugated pipes also can be bent as needed, largely avoiding leak-prone connections.  In Tokyo, the authorities replaced the existing service line infrastructure with Type 316 stainless steel pipe and made other improvements to the system. As a result, the water losses between 1980 and 2013 were reduced from 15.4% to 2.2%. The volume of the leaked drinking water was reduced from 260 million cubic meters to 33 million cubic meters per year.  Other cities, including Taipei and Seoul, have seen similar results.

Resources

Buildings

• Baddoo, N. R. and Biddle, A.R., “Steel Package Water and Waste Water Treatment Units”, The Steel Construction Institute, Berkshire, UK, 2012, 54 pages
  A publication on the use of stainless and carbon steel in on-site water and waste water treatment relative to other options.

• Houska, C. M. and Young, S. Y., “Comparing the Sustainability of Architectural Metals”, The 50^th Annual CSI Show and Convention, Las Vegas, NV • March 28 – April 1, 2006
  This paper includes data on run-off from various types of roofing materials.

Corrosion Performance in Soil

• Corrosion Resistance of Stainless Steels in Soils and Concrete (EuroInox)
• Japanese soil corrosion data, JSSA/Nickel Institute (12005)
  • Vol 1 summary of stainless steel, carbon steel, copper and lead corrosion data from 25 locations
  • Vol 2 test location data and photographs

• US Government Corrosion data

• • Adler Flitton, M.K. and Yoder, T.S., “Long-Term Underground Corrosion of Stainless Steels”, Idaho National Laboratory /NACE 2007
  • Underground Corrosion After 32 Years: A Study of Fate and Transport

Water Lines & Tanks

• Kinsman, N., Matheson, R., Coates, G., Esaki, S., “Reducing water loss with corrugated stainless steel service pipe”, 1st International Conference on Energy and Material Efficiency and CO2 Reduction in the Steel Industry, page 424
• A Workable, Lasting Solution for Water Losses through Leaking Water Pipes (ISSF) 

  Brochure on water line connections between main line pipes and buildings.

• Stainless Steel Service Pipes:A proven solution to water loss and water quality everywhere (IMOA/Nickel Institute)
• Stainless Steel – When Health Comes First (EuroInox)

  A paper focused on the human health considerations of applications in direct contact with the human body, food handling, plumbing, and pharmaceutical, food and beverage production.

• Winkler, H., “The stainless steel lining of drinking water reservoirs –Initial erection and refurbishment” (EuroInox)
• Cutler, P., “Stainless steels and drinking water around the world” (EuroInox)

  A paper summarizing over 30 years of experience with stainless steel in the water treatment, storage and distribution.

• Boneschi, V. and Quazzo, A., “Stainless steel in potable water systems: the Italian Experience” (EuroInox)

  A paper on the water taps, concrete tank linings, water main rehabilitation

• Selection and use of stainless steels in water systems (EuroInox)

  A paper on water treatment and supply lines.

Download a free Stainless Steel Library (zip file, 735 MB) with over 550 pdfs covering building and construction applications, selection, specification, fabrication, sustainability and other common questions.

For previous issues or to subscibe to the e-newsletter, please visit the archive page.

IMOA is an AIA continuing education system approved provider with eight 1-hour programs that are registered for both live face-to-face and distance learning credit.

1. Stainless Steel Sustainable Design
2. Bioclimatic Design With Stainless Steel Weather Screens
3. Stainless Steel Structural Design
4. Stainless Steel Specification For Corrosive Applications
5. Deicing Salt: Stainless Steel Selection to Avoid Corrosion
6. Stainless Steel Finish Specification
7. Advanced Stainless Steel Specification and Problem Avoidance
8. Specification of Stainless Steel Finishes and Grades For Corrosive Applications
9. Planning for Disaster: Material Selection for More Resilient Design

For more information or to schedule a workshop contact Catherine Houska, 412-369-0377 or email chouska@tmr-inc.com.

IMOA (International Molybdenum Association) is a non-profit industry association, which provides technical information to assist with successful specification of molybdenum-containing materials. Molybdenum is an element. When it is added to stainless steel, molybdenum increases its resistance to corrosion caused by deicing salts, coastal atmosphere and pollution.

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In providing consultation or other assistance with respect to technical issues, any consultation, assistance or material is provided for the general information of the recipient and should not be used or relied upon for any specific application without first securing competent advice. IMOA and their respective employees, consultants and members (i) make no representation or warranty, express or implied, of any kind with regard to such consultation, assistance or material including no representation or warranty of  suitability for any general or specific use; (ii) assume no liability or responsibility of any kind in connection  therewith; and (iii) disclaim any and all liability for any claim that arises therefrom.