Calculators and Tools

Water Conversion Calculators

Handy online calculators to figure out water flow or volume. 

• Water Calculators for Common Flow/Volume Formulas (Western Water) - The calculators are provided by Western Water, a non-profit and University collaboration.

Water Planning and Audit Tools

The following calculators help estimate water usage for landscaping and home use.

• Irrigation Water Budget Calculator (Irrigation Water Management Society) - Use these water budget calculators to estimate how much supplemental water a lawn needs to stay green and healthy, based on the size of your irrigated landscape and yearly weather averages for the Seattle area. The Intermediate calculator helps you compare your actual water use with your landscape's estimated watering requirements.  Household Water Use Calculator
• Water Conservation Program Model (SWFWMD) - this online calculator is designed to illustrate the potential effectiveness of various water conservation programs. It calculates estmated program costs and water savings benefits associated with differenct water users and conservation measures.
• Water Use Calculator (City of Tampa) - Understanding where and how much water we use is the first step in beginning to conserve one of our most precious resources. This simple home water check-up will allow you to track your household consumption, both indoors and outdoors. After calculating your water use patterns, you can begin conserving in ways that work best with your lifestyle.
• Water Audit Software (AWWA) - version 4.2 is available for free download from the AWWA web site.
• Water Conservation Tracking Tool (AWE) - This excel-based model can evaluate water savings, costs, and benefits of conservation programs. It was designed for water utilities and is available free of charge to Alliance members
• CheckCalcs (Veritec) - water audit software for identifying leakage and pressure management opportunities.
• Global Water Tool - this set of tools was developed by the Global Business Council for Sustainable Development. The tools compare a user's (company's) water use with validated water and sanitation availability information on both a country and a watershed basis. The tool also includes locations of biodiversity hot spots. Special versions of the tool evaluate power utilities and oil and gas.

Water Savings Calculators

The water footprint is an indicator of water use that looks at both direct and indirect water use of a consumer or producer.

• Pre-Rinse Spray Valve calculator (FSTC) - a simple cost calculator from the Food Service Technology Center to determine water and energy savings due to PRSV retrofit.
• Water Savings Calculator (Laundrywise) - for common area laundry rooms.
• Calculate Your Water Savings (EPA) - the WaterSense website contains a tool for calculating water savings due to retrofit of faucets, showerheads, and toilets.
• Home Water Works (AWE) - the water efficiency web site features an advanced household water calculator that gives the best and most relevant information about conserving water at home. The tool estimates home water use and recommends ways to increase water efficiency. The tool was created by the Field Museum and modified by the Alliance for Water Efficiency.

Water Footprint Calculators

The water footprint is an indicator of water use that looks at both direct and indirect water use of a consumer or producer.

• Water Footprint Calculator (Water Footprint Network) - The water footprint of an individual, community or business is defined as the total volume of freshwater that is used to produce the goods and services consumed by the individual or community or produced by the business.     

• H2O Conserve Water Calculator (H2O Conserve) - an interactive tool  designed to help you figure out how much water you use, how you use it and how you can use less.

• Waterprint (Forester Media) - an iPhone application that calculates how much water is imbedded in your daily activities, including what you wear, eat and drink.

Water Energy Calculators

The following calculators comapre water usage between conventional and solar water heaters.

• Solar Water Heating Calculator (Texas State Energy Conservation Office) - Use this calculator to explore the energy usage of your water heater, and to estimate whether a solar water heater could save you money. 
• Solar Cost Savings Estimates (Energy Matters, LLC) - Estimate the price, savings, and system size of solar energy systems to produce electricity, heat your water, or heat your spa or pool. This service is a non-profit project of Energy Matters LLC, developed with support from several non-profits and government agencies.
• Energy Cost Calculator for Electric and Gas Water Heaters (DOE) - Estimate the lifetime energy savings of electric and gas water heaters with various levels of energy efficiency.
• Energy calculator for water flow heating including cost (Lennetech) - With this calculator you can calculate the energy you will need to heat water with a certain flow. You can specify starting temperature and desired end temperature of the water. It also calculates the cost of heating when using electricity or natural gas heating for the water.
• Water-Energy Toolkit: Understanding the Carbon Footprint of Your Water (River Network) - this web site includes the showerhead comparison calculator, community water-energy savings calculator, toilet comparison calculator, water heating calculator, and new water source impact tool.
• More Water-Energy Tools (various) - this River Network web site contains links to the water to air models (Pacific Institute), personal water-energy-climate calculator (POLIS Water Sustainability Project), water savings and energy calculator (U.S. EPA), water-energy sustainability tool (UC Berkeley), and water conservation tracking tool (AWE).
• Watergy (FEMP) - calculator that considers energy savings embedded in water conservation technologies e.g. pumping energy and energy required to heat hot water.  The Watergy tool is currently being updated (Aug2011).

Rainwater Calculators

The following calculators can help determine the amount of rain water that can be harvested in particular locations.

• Rainwater Calculator (Lennetech) - A program to calculate the amount of rain water (precipitation) that will fall on a certain surface (your roof or premises). You can add the cost of mains or tap water per M3 to evaluate the cost savings per year if this rainwater is collected and used instead of drinking water.

• Rainwater Harvesting Calculator (University of Washington) - A rainwater harvesting (RWH) calculator to help Washingtonians size their RWH system based on the typical climate where they live.

Water Inefficiency Calculators

Use the following calculators to estimate water leakage and inefficency.

• Leak Loss Calculator (American Water Works Association) - Estimate Leak Loss using the AWWA’s Waterwiser Drip Calculator.

• Drip Accumulator (USGS) - how much water does a leaking faucet waste?