1. Desalination Thematic Unit – Day 1
Unit Conversions
Desalination Thematic Unit – Day 1

2. Some Crucial Units of Measurement
Gallons
Liters (Litres is an alternate spelling)
Acre
Acre-Foot
Dollars per Gallon (Dollars/Gallon)
Dollars per Liter (Dollars/Liter)

3. Gallons and Liters
Gallons are a unit of volume in the customary or English system of measurement.
Liters are a unit of volume in the metric system of measurement. In the metric system of measurement, the amounts of each smaller unit that equal a larger unit follow a pattern based on multiples of 10.

4. Converting Gallons Within Customary System
1 Gallon = 4 Quarts 1 Quart = 2 Pints 1 Pint = 2 Cups 1 Cup = 8 Fluid Ounces

5. Converting Liters Within the Metric System
1 Kiloliter = 1,000 Liters 1 Hectoliter = 100 Liters 1 Dekaliter = 10 Liters 1 Liter = 10 Deciliters 1 Liter = 100 Centiliters 1 Liter = 1,000 Milliliters

6. General Rules – Converting Units in Same System
If you are converting from a smaller unit to a larger unit: For example, going from quarts to gallons: 28 quarts = _____ gallons Going from the given unit to the new unit, we are going to a LARGER unit……so it will take LESS OF THEM to make the same amount……we want our number to get smaller, so we divide. We divide by how many Quarts make a Gallon. We divide by 4, so it is 7 gallons.

7. General Rules – Converting Units in Same System
If you are converting from a larger unit to a smaller unit: For example, going from Liters to Milliliters: 24 Liters = _______ Milliliters Going from the given unit to the new unit, we are going to a SMALLER unit……so it will take MORE OF THEM to make the same amount……we want our number to get larger, so we multiply. We multiply by how many Milliliters make a Liter. We multiply by 1,000, so it is 24,000 milliliters.

8. Converting Units Between Systems
Since GALLONS and LITERS are members of entirely different systems of measurement, we have an approximate conversion of how many liters would be equal to one gallon.
Approximately 3.79 liters = 1 gallon.
We would convert between LITERS and GALLONS the same way we convert between units of the same system of measurement.

9. Converting Between Liters & Gallons
Let’s say we wanted to find out how many liters were in 58 gallons.
58 gallons = ___ liters
We are going to the SMALLER unit, so it will take MORE OF THEM. So we will want to MULTIPLY by the number of liters. So, 58 × 3.79 = So, there are approximately liters in 58 gallons.

10. Converting Between Liters & Gallons
Let’s say we wanted to find out how many gallons would be equal to 8,540 liters.
8,540 liters = ____gallons
We are going to the LARGER unit, so it will take LESS OF THEM. So we will want to DIVIDE by the number of liters. So, 8,540 ÷ 3.79 = 2,253.3, roughly. So, there are approximately 2,253.3 gallons in 8,540 liters.

11. Acres
An ACRE is a unit that is used to measure units of area, usually on land. An acre is equal to 43,560 square feet. The shape of the area or its dimensions do not matter, only the area of the space. The most common dimensions of an acre are 660 feet × 66 feet……in other cases, this can be referred to as ‘one furlong × one chain’. If we had an acre that was a perfect square, its dimensions would be approximately feet × feet; or often called 209 feet square.

12. Acre-Feet
An ACRE-FOOT is a shape that is a rectangular prism. This rectangular prism would have bases that equaled one acre, and the depth would be one foot. Each of these diagrams represents an acre-foot.
1 foot
1 foot
feet
66 feet
feet
660 feet

13. For reference – ECMS field is about 2 acres!

14. Acre-Feet and Gallons
One Acre-Foot of Water is about 325,000 Gallons 325,000 Gallons = 1 Acre-Foot ____Gallons = 25 Acre-Feet? 186,875,000 Gallons = ____Acre-Feet? One Acre-Foot of Water is about Cubic Meters

15. For reference - ECMS Field is about 2 acres.

16. Dollars per Gallon 1,100 dollars 325,000 gallons
It is stated that the average cost to turn 1 acre-foot of salt water into fresh water is $800 - $1,400. If 1 acre-foot is about 325,000 gallons of water, we can use this to find out a cost per gallon. I am using $1,100 as an average cost to convert 1 acre-foot of water.
1,100 dollars
= 1,100 ÷ 325,000 = dollars per gallon
325,000 gallons

17. Cost to Convert Water
What if there were a need to convert 600 acre-feet of water? Let’s walk through the calculations: 1 acre-foot of water = 325,000 gallons. 600 × 325,000 = 195,000,000 gallons If the average is $1,100 for 325,000 gallons, then we can multiply $1,100 x 600 to calculate the cost per acre-foot…..$1,100 × 600 = $660,000. It would cost a total of $660,000 to convert this amount of water.

18. Dollars per Liter
Since we know that 1 Gallon is approximately liters, if an amount given is in liters, divide by to get gallons…….if it is in gallons and we need liters, we can multiply by 3.79!