Track the total metered water use for each subsystem in your building in the same manner that total building consumption is tracked in Option 1. 

The most common metering choices for Option 2 are landscape irrigation and cooling towers. One reason is that utilities will often provide a discount on sewer charges for water consumption from these uses, which can mean significant financial savings.

You can earn an additional point by pursuing Option 2. You’ll need to meet the requirements for Option 1, and install submeters for at least one water subsystem, such as the following:

Landscape irrigation
Indoor plumbing and fixtures
Cooling tower makeup water
Domestic hot water
Process water.

Option 2: Submetering

In some buildings, performing readings on a daily basis may be desirable. For example, many hotels do this because use of domestic hot water is a large load, in terms of both water and energy consumption, and it’s worth catching leaks or other issues right away.

Simply relying on utility bills that provide monthly consumption data does not meet the credit requirements, because the measurement interval is too long.

Project buildings usually meet the Option 1 requirement by adding the required weekly meter readings to the operations personnel’s standard maintenance rounds.

Implement a tracking process to collect water usage data on at least weekly intervals from water meters. You can record data automatically with data logging equipment or by manual meter readings.

In most cases achieving Option 1 is cost-neutral if the building already has a whole building meter. Some staff time will be needed, however, to manage weekly meter readings.  

Achieving Option 1 is usually easy, except in campus or multi-building situations, where metering at the building-level may not be in place or easily installed.