PERSONAL/HOUSEHOLD WATER RESOURCE USE ASSESSMENT #5

OBJECTIVES: 
1.  Calculate/estimate the resources that you or your household uses on a daily or yearly basis.
2.  Appreciate  the fairly large amounts of resources needed to support your life-style.
3.  Recognize methods for decreasing your use of resources.

INTRODUCTION:  In this exercise, you will be introduced to various water resources which are used to support the lifestyles that we are accustomed in the United States.  You will calculate the amount of water resources that you personally use, as well as, the amounts calculated on a per capita basis.  The per capita amounts are used indirectly by you because of the manufacturing, industrial, and agricultural activity needed to support society in general.  For the per capita calculations, assume that the population of the United States is 250 million.  Take whatever figure is given for the entire U. S. and divide by 250 million to get the per capita amount.

INVENTORY # 1:  WATER USED TO TAKE A SHOWER or BATH

     Does a shower or bath take more water?   Find a small pail and use a large measuring container to find the volume of the pail.   Helpful conversion units:  2 cups = 1 pint; 2 pints = 1 quart; 4 quarts = 1 gallon;   1 quart = 0.946 liters.              Show method used to find the volume of the pail.
                                 VOLUME OF PAIL: __________________

     Turn on the shower or bath faucet to the normal amount of water that you use.  Measure the time it takes to fill the pail with water when you hold it up close to the shower head/faucet.  Then measure the total time that you normally stay in the shower or to fillthe bath tub. 

                         		SHOWER               BATH
              
TIME TO FILL PAIL:  	    ___________            ___________

TIME:                   	    ___________           ___________

     Calculate how many pails of water would be filled during the time it takes for a shower or to fill the bath tub.  Finally calculate the volume of water in gallons used for a shower or bath.

PAILS OF WATER       ___________           ____________

GALLONS OF WATER:   ___________           ____________

    Count the number of showers/baths on the average per day in your house.  Then calculate the volume of water used per day and then per year.

NUMBER OF SHOWERS/BATHS PER DAY:  _________________

VOLUME OF WATER USED PER DAY:       ________________

VOLUME OF WATER USED PER YEAR:     _________________
INVENTORY # 2:  WATER USED TO FLUSH A TOILET

     Use a ruler to measure the outside dimensions in inches of the toilet tank.  Measure the width and length first.  The height should be measured only to the approximate level of the water inside.  Subtract about a half inch for the thickness of the porcelain.  Calculate the volume of the toilet tank in cubic inches.

LENGTH:  ________   WIDTH:  ______   HEIGHT:  __________

VOLUME OF TANK:  ______________ in cubic inches.

     Find the volume of the tank in gallons.  1 cubic foot = 1728 cubic inches;  1 cubic foot = 7.44 gallons.  Add about 10% more to the tank volume to give the amount used per flush since water runs in before it is totally empty.

VOLUME OF TANK IN GALLONS:  _______________

VOLUME OF WATER PER FLUSH:  _______________

     Keep track of how many time the toilet(s) are flushed per day in your house.  Do this for a couple days to get an average.  Calculate the volume of water used to flush the toilets per day and per year.

NUMBER OF DAILY TOILET FLUSHES:  ______________

VOLUME OF WATER USED PER DAY:   ______________

VOLUME OF WATER USED PER YEAR:  ______________


INVENTORY # 3:  TOTAL HOUSEHOLD WATER USE

     Find your water bills and read the amount of water used which is usually given in thousands of gallons.  The bill is usually for a 3 month period.  Try to find the last four bills for a year period of time. From these bills, make the following calculations:

VOLUME IN GALLONS FOR A YEAR:  _______________

VOLUME IN GALLONS FOR A DAY: _________________

NUMBER OF PEOPLE IN HOUSE:     _________________

VOLUME OF WATER PER PERSON PER YEAR:  ____________

     WATER USAGE:  The two common measures of water use are withdrawal and consumption.  Water is withdrawn when it is taken from a surface or groundwater source and taken to the place of use.  Water is consumed when it is no longer available for reuse because of evaporation, contamination, seepage into the ground, or used by plants and animals.  About 23% of water withdrawn in the U.S. is consumed.

                
		124 Trillion gallons of  water per year withdrawn in U.S. - 1984

QUES. 1:   Calculate the per capita water withdrawn per year (assume a population of 250 million).  One trillion = 1012

QUES. 2:  Calculate the daily water withdrawn per person.

QUES. 3:  To find a more realistic number of gallons per day per person, calculate 10% of the above answer which represents the public water withdrawn.

                 
		28.5 Trillion gallons of water per year consumed in U.S. - 1984  

    Although about 80% of the water withdrawn is used for irrigation and electric power cooling, only uses by irrigation lead to about half of the water consumed.

QUES. 4:  a. Use the public percentage to calculate the gallons of water consumed by the public.
	b.  Then find the gallons of water consumed by the public per day.