This is a legacy version of the WELL Building Standard. Please check the latest version here.

Fundamental water quality

Two properties of water—turbidity and total coliforms—serve as indicators for the possible presence of many harmful contaminants. High turbidity can provide food and shelter for germs, and may also indicate that a building’s filtration system is not working properly. Removing turbidity may also remove harmful pathogens such as protozoa. Another test is the measurement of total coliforms. Coliform bacteria are naturally present in the environment and are generally considered harmless. However, their presence in water suggests that water may contain more dangerous pathogens, including bacteria, viruses and protozoa. Exposure to these pathogens through water containing coliforms can lead to adverse gastrointestinal effects such as diarrhea, vomiting, nausea and cramps.

Part 1: Sediment

All water being delivered to the project area except water not designated for human contact meets the following requirements:

a.50 Turbidity of the water sample is less than 1.0 NTU.
Part 2: Microorganisms

All water being delivered to the project area except water not designated for human contact meets the following requirements:

a.54 Total coliforms (including E. coli) are not detected in the sample.
Immune
Urinary
Digestive
Nervous

Applicability Matrix

Core & Shell New & Existing Buildings New & Existing Interiors
Part 1: Sediment P P P
Part 2: Microorganisms P P P
Commercial Kitchen Education Multifamily Residential Restaurant Retail
Part 1: Sediment P P P P P
Part 2: Microorganisms P P P P P

Verification Methods Matrix

Letters of Assurance Annotated Documents On-Site Checks
PART 1 (Performance)
Sediment
Performance Test
PART 2 (Performance)
Microorganisms
Performance Test
50

U.S. Environmental Protection Agency. National Primary Drinking Water Regulations. EPA 816-F-09-004. Published May 2009. Washington, D.C.

30.1.a

The US EPA National Primary Drinking Water Regulations notes that for systems that use conventional or direct filtration, "samples for turbidity must be less than or equal to 0.3 NTU in at least 95 percent of the samples in any month".

54

Office of Water. 2012 Edition of the Drinking Water Standards and Health Advisories. Washington D.C.: U.S. Environmental Protection Agency; 2012: 2, 3, 5-11.

30.2.a

The EPA 2012 Edition of the Drinking Water Standards and Health Advisories set a Maximum Contaminant Level Goal for Total Coliforms at 0.