1.1: Applying the Math of UDA
- Page ID
- 7125
“Will I ever use UDA in real life?” This sort of question usually pops into the heads of students in all subjects, but in math, it happens quite often. In a practical sense, UDA can be looked at as converting between currencies. If you travel to Europe for example, you will want to know how many Euros equal a dollar. Or you may want to figure out how fast you are driving, in which case you would need to convert kilometers per hour into miles per hour.
However, in the “world” of water, converting of units is commonplace. The following few questions are written with the perspective of “real world” scenarios.
Exercises
A water utility manager has been asked to prepare an end of year report for the utility’s Board of Directors. The utility has 4 groundwater wells and two connections to a surface water treatment plant. Complete the table below.
Source of Supply |
Flow Rate (gpm) |
Daily Operation (Hrs) |
Total Flow (MGD) |
Annual Flow (AFY) |
Well 1 |
800 |
10 |
||
Well 2 |
1,000 |
8 |
||
Well 3 |
650 |
16 |
||
Well 4 |
2,250 |
11 |
||
SW Pump 1 |
1,750 |
7 |
||
SW Pump 2 |
1,500 |
9 |
Using the information from the above problem, fill in the table below.
Source of Supply |
Annual Production (AFY) |
Cost per AF ($/AF) |
Total Annual Cost ($) |
Well 1 |
60 |
||
Well 2 |
60 |
||
Well 3 |
95 |
||
Well 4 |
95 |
||
SW Pump 1 |
450 |
||
SW Pump 2 |
450 |
||
Total Annual Cost |
A water utility has 12,300 service connections. 80% of the connections are residential, 15% commercial, and 5% industrial. Complete the following table. (Assume an average month has 30 days)
Connection Type |
Number of Connections |
Average usage per day per connection (gallons) |
Average Monthly Usage per Connection Type (CCF) |
Residential |
835 |
||
Commercial |
1,370 |
||
Industrial |
2,200 |
Based on the total combined monthly usage and a unit cost of water equaling $1.15/CCF, how much money will the utility generate in one year?