A successful water management program starts with a comprehensive strategic plan. The process for developing a strategic plan is generally the same for an individual facility or an agency. The plan provides information about current water uses and charts a course for water efficiency improvements, conservation activities, and water-reduction goals. A strategic plan establishes the priorities and helps a site or agency allocate funding for water-efficiency projects that provides the biggest impact. This best management practice (BMP) describes the general steps for creating a water management plan.
To develop a comprehensive strategic plan, the facility or agency should set specific water use reduction targets. An agency should coordinate these targets with a federal water-efficiency policy such as Executive Order (E.O.) 13693 or the Energy Independence and Security Act of 2007. The Laws and Requirements website provides a full description of the water-related laws and requirements. The strategic plan should also include senior management support for water efficiency. This can be done in two ways:
- Provide a written policy statement that ties water efficiency to the long-term operating objective of the facility or organization
- Provide staff and financial resources to track water use, maintain equipment, and implement cost-effective water use reduction projects.
Understanding the current water uses and costs is essential to a comprehensive plan. This step involves collecting water and cost data and determining a baseline that will be used to calculate cost savings and determine overall water reduction potential associated with water-efficiency opportunities.
At the facility level, this task includes the following substeps:
- Determine the marginal per-unit cost of water and sewer service
- Verify the appropriate rate structure is applied
- Identify services the utility might provide to help manage water efficiently
Utility information should include the following for potable and nonpotable water:
- Contact information for all water and wastewater utilities
- Current rate schedules and alternative schedules that are appropriate for a particular use or facility type to ensure the best rate
- Copies of water and sewer bills for the past two years to identify inaccuracies and ensure the appropriate rate structure is applied
- Information about rebates or technical assistance from the utilities to help with facility water planning and implementing water-efficiency programs. Energy utilities often offer assistance with water-efficiency programs
- Contact information for the federal agency or office that pays the water and sewer bills
- Production information if the facility produces its water or treats its own wastewater, or both
After collecting water use data, take the following substeps:
- Determine a baseline annual water use for a specific year or an average water use over several years. If monthly data are available, plot the monthly use over time. Is water use increasing, decreasing, or steady?
- Try to determine what caused the major trends. Is there a seasonal pattern to water use? This is often the case when irrigation water is used or cooling water demand increases in the summer months. Analyzing the data in this way will help you understand current water use trends.
At the agency level, this step involves collecting detailed water use and cost data and real property inventory from all sites. These data are likely collected at the agency level per the reporting requirements of E.O. 13693. When collecting this information, consider that you need to separately gather data about potable water use and industrial, landscaping, and agricultural water use (primarily nonpotable water) that is associated with reduction targets.
An important step in creating a water management plan is to establish a water balance for the facility or agency. A water balance compares the total water supply baseline (determined in step 2) to water that is used by equipment and applications.
Estimate Water End Uses
Determining water use at the equipment or application level can be challenging. Most federal facilities have metered data for total water supply but may have limited or no submetering data about component uses. The following five steps outline the process for determining water use at the equipment level:
- Create an inventory of all water-using activities. Use the the Federal Energy Management Program's BMPs list as a starting place to identify major equipment types. Tap the expertise of others at the facility who have direct knowledge of building mechanical systems and process equipment to generate a complete inventory.
- Perform a walk-through audit of the facility to identify all significant water-using processes and associated operating characteristics. As part of the walk-through audit, note the operating schedule, flow rate, model number, and condition for each piece of equipment. You can also use a bucket and stopwatch and make a quick, rough estimate of equipment flow rate (e.g., faucets, showerheads, and once-though cooling). During the walk-through, pay particular attention to drain lines that are plumbed to floor drains in building mechanical spaces and utility chases.
Trace these back to the originating equipment to make sure they are accounted for in the water balance.
- For all water uses in the inventory, obtain any available submetered data to help quantify the particular uses
- Evaluate any seasonal patterns and compare them to the inventory of uses. Are any uses seasonal, such as cooling tower use or irrigation? The seasonal pattern of water use (peak use) can help quantify these uses
- For unmetered water end uses, create engineering estimates of water use. For example, estimate:
- Water use from plumbing fixtures (toilets, urinals, faucets, and showerheads) based on the number of occupants and daily use per occupant
- Cooling tower use based on cooling capacity and load factor (see BMP #10)
- Irrigation water use based on irrigated area and inches of water applied
- Operating equipment water use based on water use per cycle and frequency of cycles.
Develop the Water Balance
You can now create a water balance with the quantified water uses by major equipment type. Compare the sum of the end-use water consumption to the total supply. The difference between these two values represents the "losses" in the system (see figure). These losses may be a result of:
- Water leaks in the distribution system or equipment
- Inaccuracies in the engineering estimates used to determine equipment water use
- Accounting errors such as poorly calibrated meters or unit conversion problems. If the losses are more than 10% of the total water supply, further investigation is probably warranted to determine the cause of the imbalance. This may include a comprehensive leak detection program (see BMP #3).
This process will uncover the high-water-use activities, which will help you prioritize water-saving opportunities.
Based on the outcome of the water balance, the next step is to find ways to increase water efficiency and reduce water use. Use the FEMP BMPs for water efficiency as a starting point to identify operations and maintenance, retrofit, and replacement options for:
- Distribution System Audits, Leak Detection, and Repair
- Water-Efficient Landscaping
- Water-Efficient Irrigation
- Toilets and Urinals
- Faucets and Showerheads
- Boiler and Steam Systems
- Single-Pass Cooling Equipment
- Cooling Tower Management
- Commercial Kitchen Equipment
- Laboratory and Medical Equipment
- Other Water-Intensive Processes
- Alternative Water Sources
After you identify the water efficiency opportunities, perform an economic analysis to determine if the projects are life cycle cost-effective. In this analysis, use the marginal water and sewer rates identified in step 2. Be sure to also include other related costs, such as energy and operations and maintenance changes, which resulted from the measure. For example, faucet and showerhead retrofits save energy by reducing hot water use.
Use the Building Life Cycle Cost Programs software to determine the economics of energy and water projects. Also, determine the annual escalation rate of the marginal cost of water to escalate water costs in the future. Learn more about water rate escalations across the United States.
Ensure water supply, wastewater, storm water issues, and water efficiency BMPs are taken into account at the earliest stages of planning and design for renovation and new construction. Consider developing equipment specifications that target water-efficient products so they are automatically purchased for retrofits, renovations, and new construction. As an example, NASA's Marshall Space Flight Center implemented a product specification for water-efficient plumbing products.
After identifying water efficiency projects you want to pursue, build an implementation plan. You may want to use this plan to:
- Assign teams to be responsible for implementation
- Prioritize projects based on targeted end uses
- Project a date for installing efficiency measures
- Project annual water use based on implemented efficiency projects
- Identify potential funding sources.
The implementation plan should predict if water goals can be met by the site or agency by implementing cost-effective water-efficiency measures. The plan should also include education and outreach efforts for the building occupants to help reduce water use.
Regularly review the strategic plan to make sure measures are implemented and goals are realistic and are being accomplished. Make sure water use reduction targets are being met to fulfill current federal policies such as E.O. 13693.
A key element of good water management is tracking water use. Install submeters on water-intensive processes, such as cooling towers and irrigation systems, to help manage these processes better and meet annual reporting requirements. You should assign someone to be responsible for tracking ongoing water use. Continue to plot total water use as new water bills become available. Also plot any available submetered data. Evaluate trends and investigate and resolve any unexpected deviations in water use. Track water use reductions and publicize your success. See Metering in Federal Buildings for more information.
Consider including water emergency and drought contingency plans that describe how your facility or agency will meet minimum water needs during emergency, drought, or other water shortages. Consider assessing the site for future water availability risks that are associated with climate change. At the agency level, this information can be used to target sites that have or may have water availability risks to help prioritize sites for funding water-efficiency projects.