How specifications impact water quality

Architects and designers have long understood that specifications shape performance, from energy and water efficiency to health and safety for those utilizing built spaces. Increasingly, that responsibility extends to drinking water. The decisions made at the product selection stage determine whether occupants receive safe, high-quality water or are unknowingly exposed to contaminants.

Today, most buildings still deliver unfiltered water, and it’s the result of what is (and isn’t) specified.

The genesis of the problem

Across the U.S., many municipalities meet strict regulatory standards, and it’s common to hear people say, “My city has safe water.” At treatment plants, that’s often true, but matters are different at water sources. Widespread exposure to contaminants such as lead, PFAS, and microplastics continue to raise concerns about the quality of drinking water delivered inside buildings. For instance, more than 47 million children are exposed to lead in water daily, and PFAS have been detected in the blood of 99% of Americans.
 
Several factors contribute to contaminant exposure:

• Distribution systems can reintroduce contaminants. As water travels through aging underground pipes, it can pick up materials like lead and other debris, especially in cities with older service lines or plumbing.
• Building plumbing creates additional risk. Once inside a building, water moves through internal systems that are rarely monitored as closely as municipal infrastructure. Stagnation, outdated fixtures, and certain piping materials can contribute to contamination, including by lead and other metals, microplastics from plastic components, and bacterial growth in low-use areas.
• The “last mile” is largely untested. Water is typically tested at centralized points, not at every faucet or fountain. This means contaminants introduced within buildings often go undetected.
• There is sometimes a gap in specification, not intent. Utilities may deliver compliant water, but without intentional building-level design, like filtration, monitoring, and material selection, quality can degrade before the point of use.

In practice, this means a school, office, or hospital in a “safe water” city can still expose occupants to contaminants, not because treatment failed but because infrastructure along the way reintroduced contaminants.

Invisible contaminants, real-world impact

Unlike other building system risks, water contaminants are often invisible. Many occupants are unaware that they may be drinking unfiltered, basic tap water. And many architects and engineers assume all bottle fillers are filtered when making product selections.

Lead exposure has no safe threshold and is linked to irreversible developmental impacts. PFAS—often referred to as “forever chemicals”—persist in the human body and have been associated with cancer and hormonal disruption. Microplastics, now found in human blood and organs, represent an emerging and still-evolving health concern. Despite this, point-of-use filtration is still not standard in many project specifications.

Regulation is already reshaping design requirements

Drinking water quality is no longer a future concern; it is an active regulatory focus. Across the U.S., more than 100 state and federal bills are addressing water safety, with over 30 states advancing new requirements.

Programs like Michigan’s “Filter First” legislation are establishing a clear precedent, calling for features such as mandatory filtered bottle filling stations in schools, defined ratios of units per occupants, filter maintenance documentation, and ongoing water quality testing

For architects, this signals a shift. Specifying unfiltered systems today may result in costly retrofits tomorrow, often under compressed timelines and increased scrutiny. Below are some specific risks associated with specifying unfiltered systems.

• Liability risk: As regulations tighten, previously acceptable systems can quickly become non-compliant. Specifications may be revisited years later under legal or regulatory pressure.
• Financial risk: Retrofitting drinking water systems after occupancy can cost three to five times more than incorporating filtration during initial construction.
• Reputational risk: Water quality issues can escalate quickly in the public eye. A single incident shared through social media or news coverage can have lasting implications for a building, institution, or brand.

Real-world impacts of delayed action

Across the country, school districts and institutions have already experienced the consequences of unfiltered systems: Milwaukee Public Schools invested over $1.6 million in retrofits following lead contamination. And the Houston Independent School District faced multi-million-dollar remediation costs after widespread testing failures.

These are not isolated events; they represent a growing pattern tied directly to specification and standards decisions. 

Occupant expectations are changing

Bottle filling stations were introduced about 15 years ago. They weren’t largely adopted through code changes or requirements but rather because architects and building owners recognized their value to occupants. Today, filtration is following that same path: a proactive design choice driven by performance, health, and user expectations—not just compliance.  

Occupants expect bottle filling infrastructure, and they often avoid unfiltered fountains altogether. Wellness-focused design is now a competitive differentiator. For many users, particularly younger generations, filtered water is not optional. It is expected. (How might you tell if a drinking water solution is filtered? Look for the filter status lights! Learn more here.)

Designing for what’s next

The trajectory of drinking water systems is moving toward higher filtration performance, easier maintenance, and smarter monitoring. Advancements in filtration technology now enable:

• Reduction of lead, PFAS, and microplastics
• High-capacity filters that reduce maintenance frequency
• Simplified service access that minimizes disruption
• Connected systems that allow real-time monitoring and preventative maintenance

These innovations are not just product improvements; they enable easier selections.

A new standard for specification

As regulation expands, occupant expectations rise, and long-term costs become clearer, specifying filtered drinking water systems is quickly becoming the standard of care. Architects are uniquely positioned to lead this shift.

By clearly indicating filtration selections on your specifications and plumbing schedules, you can help design teams:

• Improve occupant health and safety
• Reduce long-term operational costs
• Future-proof buildings against evolving regulations
• Strengthen the overall value and performance of their projects

Take the lead for water quality

Drinking water quality is no longer a background consideration or just a fixture required by code; it is a defining element of building safety and performance. And occupant health is determined by your specifications.

The buildings being designed today will serve occupants for decades. The question is whether they will deliver water that meets the expectations now and for future generations.

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