You would be making a big mistake if you think that hard water is an issue only in your region. To be honest, it is a worldwide issue. And how does it impact buildings? Well, first, the plumbing system gets affected, and consequently, building performance declines. Then there are the maintenance costs.
Generally, hard water is characterized by elevated concentrations of magnesium and calcium. While it doesn’t directly put our health at risk, it affects the long-term effectiveness of MEP infrastructure and equipment. These impacts are significant.
Studies confirm that in many regions of the world, water hardness goes even beyond 200 mg/L. Such concerning figures call for meticulous design strategies. On top of that, it is also crucial to incorporate high-performance water treatment activities, along with a detailed understanding of relevant sustainability and regulatory guidelines.
Hard Water Explained for AEC Professionals
Hard water is classified into four categories: soft, moderately hard, hard, and very hard. Each category is defined through specific hardness levels, measured in “mg/L as CaCO3.”
0 to 60 mg/L as CaCO3 denotes the soft category, while 61 to 120 mg/L as CaCO3 is considered moderately hard, followed by 121 to 180 mg/L as CaCO3 as hard, and greater than 180 mg/L as CaCO3 as very hard.
It is essential to recognize that elevated hardness levels directly reflect reduced inflow, increased scaling, lower heat-exchange effectiveness, and longer maintenance intervals. All of these ultimately affect a building’s lifecycle expenses and the client’s satisfaction level.
Usual Issues in Building Systems
Hard water contributes to some common issues in building systems. The first most common one is loss of pressure and clogging in domestic water and hydronic piping. Since modern buildings have water heaters, chillers, and cooling towers, hard water reduces their heat-transfer capacity.
On the other hand, fixtures, valves, and pumps degrade much faster than usual due to hard water. Real-world observations also confirm that, due to this issue, energy consumption and detergent use increase considerably. Last but not least, hard water leads to mineral spotting on glass surfaces and other fixtures.
Water Treatment and Softening Options
One of the most commonly used solutions for hard water issues is salt-based ion-exchange softeners. They substitute calcium and magnesium ions with potassium or sodium. This process is performed using a resin bed. In fact, this is one of the most reliable, proven approaches for high-hardness water. Whether residential or commercial, this solution is effective in both cases.
The next known solution is salt-free water conditioners. They utilize catalytic or template-supported crystallization media to mitigate mineral adhesion. This type of solution is chemical-free and requires little maintenance. These conditioners are ideal for green building projects and for moderate water hardness.
Dual-tank softeners are the next best solution for addressing hard water issues. They use two resin tanks in alternate cycles. This solution guarantees nonstop soft water availability. Dual-tank softeners are ideal for hospitals, hotels, and industrial infrastructure, as their high flow capacity is well-suited to these applications.
Magnetic and electronic descalers are also widely used to treat hard water. They utilize RF or electromagnetic fields to change the behavior of mineral crystallization. This solution comes with no added chemicals and is non-invasive. Keep in mind that this solution is extremely easy to retrofit into prevailing systems.
Some additional filtration strategies help resolve hard water issues more effectively. Activated carbon filters can be used to enhance taste, remove chlorine, and reduce odor. Sediment filters are the next option, ensuring protection for softeners and fixtures from rust, sand, and silt. Reverse osmosis is also quite common now. It delivers highly purified water for healthcare, laboratory, and food service use. Lastly, UV sterilization is vital for private wells or other water sources that are microbiologically vulnerable.
What MEP Engineers Need to Consider in Terms of Design
For MEP engineers in the USA, certain aspects should be taken into consideration when designing a MEP system that avoids hard water issues. First of all, they need to consider the data on local water quality. They need to obtain information regarding TDS, hardness, and pH values at the very beginning of the design process. System sizing is another important factor. It should be done based on real-life demand and peak flow rates.
Before designing, MEP experts should assess the impact of pressure drop on softeners and filters. When it comes to considering drainage provision, they must ensure that backwash and regeneration lines meet the relevant code guidelines. For maintenance and monitoring awareness, MEP specialists should first review the BMS compatibility. Finally, these engineers must be highly meticulous about following regional environmental discharge and health norms.
Planning for System Durability and Upkeep
Dealing with hard water issues in the best possible way must involve preparing for the system’s durability and maintenance. The first step of this planning consists of inspecting and cleaning resin beds according to the manufacturer’s guidance. Replacing filters in a timely manner is key to averting flow limitations. One should sanitize the water tanks at least once every year to eradicate microbial growth. The final task in this planning journey is to document service frequencies within the provisions of the facility manual related to operation and maintenance.
Designing with Sustainability in Mind
There is now a strong focus on net-zero and water-positive approaches. This allows AEC teams to prioritize design sustainability through highly efficient, low-salt systems. Besides, they should also implement salt-free and hybrid technologies in regions with stringent discharge regulations. Collaborative water reuse techniques should also be adopted to diminish softener load and wastewater production.
Final Notes
So, hard water is a significant issue for AEC teams since it directly affects a building’s efficiency. It reduces equipment performance and amplifies overall lifecycle expenditures. Addressing this challenge revolves around precise sizing, informed design choices, and the incorporation of effective, eco-friendly treatment solutions.
If your AEC firm grapples with this issue in most projects, partner with National MEP Engineers to leave this concern behind for good. Our MEP experts ensure your building systems are free from hard water issues for long-term, reliable performance.
