Water treatment

BACKGROUND

There are many types of contaminants that may compromise water quality, from pathogens and heavy metals to pesticide and herbicide residues. While routine testing helps to keep track of potential pollutants, sampling alone cannot guarantee the elimination of all risk. Disruptions to water supply, droughts, flooding and construction and infrastructure changes can temporarily affect water quality. Therefore, implementing and maintaining appropriate water treatment systems - including carbon filters, sediment filters and UV sanitization - is key in order to continuously deliver high quality water.

Immune

Digestive

Part 1
Organic Chemical Removal

VERIFICATION

All water being delivered to the project area for human consumption is treated with the following:

a.¹⁸⁷

Activated carbon filter.

Letter of Assurance
MEP On Site
Spot Check

Part 2
Sediment Filter

VERIFICATION

All water being delivered to the project area for human consumption is treated with the following:

Filter to remove suspended solids tested with standard NSF 42 or EN 13443-2.

Letter of Assurance
MEP On Site
Spot Check

Part 3
Microbial Elimination

VERIFICATION

All water being delivered to the project area for human consumption is treated with one of the following:

a.¹⁸⁸

UVGI water sanitation.

Filter rated by the NSF to remove or reduce microbial cysts.

Letter of Assurance
MEP On Site
Spot Check

Part 4
Water Quality Maintenance

VERIFICATION

To verify that the selected filtration/sanitation system chosen continues to operate as designed, projects must annually provide the IWBI with:

Record-keeping for a minimum of 3 years, including evidence that the filter and/or sanitizer has been properly maintained as per the manufacturer's recommendation.

Documents
Operations Schedule

Part 5
Legionella Control

VERIFICATION

A point-by-point narrative describes how the building addresses Legionella, and includes the following:

a.¹⁷⁷

Formation of a team for Legionella management in the building.

b.¹⁷⁷

Water system inventory and production of process flow diagrams.

c.¹⁷⁷

Hazard analysis of water assets.

d.¹⁷⁷

Identification of critical control points.

e.¹⁷⁷

Maintenance and control measures, monitoring, establishment of performance limits and corrective actions.

f.¹⁷⁷

Documentation, verification and validation procedures.

Documents
Professional Narrative

	Core & Shell	New & Existing Buildings	New & Existing Interiors
Part 1: Organic Chemical Removal	O	O	O
Part 2: Sediment Filter	O	O	O
Part 3: Microbial Elimination	O	O	O
Part 4: Water Quality Maintenance	O	O	O
Part 5: Legionella Control	O	O	O

	Commercial Kitchen	Education	Multifamily Residential	Restaurant	Retail
Part 1: Organic Chemical Removal	O	O	O	O	O
Part 2: Sediment Filter	O	O	O	O	O
Part 3: Microbial Elimination	O	O	O	O	O
Part 4: Water Quality Maintenance	O	O	O	O	O
Part 5: Legionella Control	O	O	O	O	O

Verification Methods Matrix

	Letters of Assurance	Annotated Documents	On-Site Assessment
Part 1: Organic Chemical Removal	MEP		Spot Check
Part 2: Sediment Filter	MEP		Spot Check
Part 3: Microbial Elimination	MEP		Spot Check
Part 4: Water Quality Maintenance		Operations Schedule
Part 5: Legionella Control		Professional Narrative

Standard Citations

**177**

**ASHRAE Standing Standard Project Committee 188. ANSI/ASHRAE Standard 188-2015: Legionellosis: Risk Management for Building Water Systems. Atlanta; 2015**
36.5.e	ASHRAE's Hazard Analysis and Critical Control Point plan for preventing building associated legionellosis includes monitoring identified control points and establishing procedures for corrective measures.
36.5.d	ASHRAE's Hazard Analysis ad Critical Control Point plan includes identifying critical control points.
36.5.c	ASHRAE's Hazard Analysis and Critical Control Point plan for preventing building associated legionellosis includes conducting a hazard analysis.
36.5.f	ASHRAE's Hazard Analysis and Critical Control Point plan for preventing building-associated legionellosis includes establishing documentation and verification procedures.
36.5.b	ASHRAE's Hazard Analysis and Critical Control Point Plan requires teams to develop at least two process flow diagrams mapping the receipt, processing and delivery of water to occupants.
36.5.a	ASHRAE's Hazard Analysis and Critical Control Point Plan requires the development of a team comprised of members who understand the building's water systems and the principles of the plan.

**187**

**Minnesota Department of Health. Water Treatment Using Carbon Filters (GAC). http://www.health.state.mn.us/divs/eh/hazardous/topics/gac1.pdf. Published 2013. Accessed June 10, 2015.**
36.1.a	The Minnesota Department of Health notes that "A filter with granular activated carbon (GAC) is a proven option to remove certain chemicals, particularly organic chemicals, from water".

**188**

United States Environmental Protection Agency Office of Water. Alternative Disinfectants and Oxidants Guidance Manual. http://www.epa.gov/ogwdw/mdbp/alternative_disinfectants_guidance.pdf. Published April 1999. Accessed June 12, 2015.
36.3.a	The US EPA's Alternative Disinfectants and Oxidants Guidance Manual notes that the optimum UV range is between 245 and 285 nm, which corresponds to UV-C radiation (200-280 nm).

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

Water treatment

BACKGROUND

Part 1 Organic Chemical Removal

Part 2 Sediment Filter

Part 3 Microbial Elimination

Part 4 Water Quality Maintenance

Part 5 Legionella Control

Applicability Matrix

Verification Methods Matrix

Standard Citations

Part 1
Organic Chemical Removal

Part 2
Sediment Filter

Part 3
Microbial Elimination

Part 4
Water Quality Maintenance

Part 5
Legionella Control