All audits involve a review of current individual customer water use practices and behaviors, and an assessment of potential water saving opportunities. A good audit will include recommendations for improvement in water use efficiencies, framed with costs and periods of payback for specific investments. Audits are conducted through a combination of data collection and assessment, augmented by a site visit where owners and/or operators are interviewed and information is collected to characterize water use. It is valuable to obtain the last two years of monthly water use data for the home and/or facility prior to the site visit such that the data can be reviewed and anomalies can be identified and investigated.
Once the site visit is completed, a model of the water use at the residence and/or facility can be developed and calibrated to measured water use over time. This model can be used to support an assessment of alternative future water use scenarios featuring different configurations of fixtures, appliances, and behaviors.
Note that system wide water audits are also a best management practice; however, these audits are performed system-wide and not for individual customers.
Residential and business energy audits have become popular and readily available over the past decade, due to the availability of energy demand reduction funding. Water audits have not been as popular or as readily available, however, given that the nature of these audit types are similar, energy and water audits can be performed concurrently to take advantage of customer availability and the combined benefits of water and energy savings. Therefore, future utility audit programs may be able to take advantage of energy audit programs to fund water audit programs.
Three types of audit procedures are provided in the CWW Guidelines of Best Practices for Municipal Water Conservation:
Residential Audits
These audits are typically provided to those residential customers that request an audit from the utility. The utility can target the high water users for promoting and recommending the audit; however, experience indicates that audits are not typically required, and are doled out to those customers that request the service.
(Guideline of Best Practices BP 13 Residential Water Surveys, Evaluations Targeted at High Demand Customers)
Industrial, Commercial and Institutional (ICI) Audits
As with the residential audits, ICI audits are typically performed on a voluntary basis. However, experience indicates that commercial sectors can be effectively targeted with audit programs, especially if the audits are accompanied by fixture giveaways that will immediate save energy and water (e.g., high efficiency showerheads and faucet aerators, pre-rinse spray nozzles). However, some national commercial organizations with multiple storefronts have policies that limit the ability of local managers to change fixtures and appliances. For this reason, ICI audits are sometimes best focused on locally owned and operated businesses including hotels, restaurants, bars, laundries, schools, etc.
(Guideline of Best Practices BP 14 Specialized Non-Residential Surveys, Audits and Equipment Efficiency Improvements)
Irrigation Only Audits
Given that home owner associations (HOAs), institutional irrigators (e.g., schools, parks, jails) and some commercial irrigators may constitute some of a utilities largest water users, and that summer peaking demands can create substantial challenges for some utilities, irrigation only audits can be significant water demand reducers. Part of the dynamic is that automated irrigation systems often waste water when left unmonitored. In additional, some organizations would prefer to pay low water costs than sacrifice green. Irrigation water audits can be effective in identifying outdoor water inefficiencies caused by broken or worn sprinkler heads, systems that operate at high pressures, properly designed sprinkler coverage, irrigation clocks that are incorrectly set, etc.
(Guideline of Best Practices BP 10 Irrigation Efficiency Evaluations)