Name: _____________________________
Date:______________________________
Southern Sierra CZO
Education Activity 6
SimWater
Background
Water managers are faced with complex systems of water storage, delivery, and
use. The following exercises demonstrate some of the main issues that water managers
are faced with in deciding who will receive water and how to use land.
Exercise 1 – Warm up
You are provided with a grid with uniform precipitation. All runoff flows toward
the “river” (blue line) that bisects the grid. Your job is to balance the amount of
precipitation that comes into the system, water consumption by agricultural and urban
users, and achieve a river flow out of the system. We will use metric units in order to
simplify calculations. Use the following table of water supply and consumption rates:
Table 1 – Water Supply and Consumption Rates (per year)
Precipitation
Agricultural Land Use
Urban Land Use
Discharge Goal
1m
1m
1m
100,000 m3
Use the colored construction paper provided to assign land for use by agriculture and
urban landscapes. Use Map 1 for this exercise. Each square represents one hectare or
10,000 m2 of land. The volume of water that falls on land from precipitation is equal to
the amount of precipitation times the area of land. For each square on the map 1 m of
precipitation falls on 1 hectare of land for a total volume of 10,000 m3 of water.
Exercise 2 – A little more complicated
In this exercise, you have two precipitation regimes, two agricultural crops with
different water consumption rates, a residential consumption rate, and a commercial
consumption rate. Use the following table of water supply and consumption rates:
Table 2 – Water Supply and Consumption rates (per year)
Precipitation 1 (light blue)
Precipitation 2 (dark blue)
Agriculture 1
Agriculture 2
Residential Use
Commercial Use
Discharge Goal
1m
0.5 m
0.5 m
2
0.5 m
1m
100,000 m3
In addition to having more precipitation regimes and consumption rates, you will
have to balance food production and population. Use the following table for food
production and population:
Created by Ryan Lucas and Erin Stacy, UC Merced
Name: _____________________________
Date:______________________________
Southern Sierra CZO
Education Activity 6
Table 3 - Food production and population
Agriculture 1
Agriculture 2
Residential Use
Commercial Use
produces food for 6 people per year
produces food for 18 people per year
provides home to 80 people
provides employment for 100 people
Use Map 2 for this exercise.
Exercise 3 – A Model California
In this exercise we will use Map 3. This map is broken into four precipitation
regimes to simulate the Coastal areas (light blue), the Central Valley (orange), the Sierra
foothills (dark blue), and the Sierra Nevada mountains (purple). We will use the same
two agricultural consumption rates and the same residential and commercial consumption
rates. Use the following table for water supply and consumption rates:
Table 4 - Water Supply and Consumption rates
Precipitation 1 (light blue)
Precipitation 2 (orange)
Precipitation 3 (dark blue)
Precipitation 4 (purple)
Agriculture 1
Agriculture 2
Residential Use
Commercial Use
Discharge Goal
1m
0.25 m
2m
3m
0.5 m
2
0.5 m
1m
100,000 m3
In addition to the food production and population guidelines provided in Exercise 2, we
can make this step more challenging by applying some land use rules to Exercise 3:
1. Due to the environmental impact of developing near a river, no residential or
commercial land use is allowed within 300 m of the river (each side of a grid box
is = 100 m).
2. In order to prevent coastal erosion and fertilizer runoff into the ocean, no
residential, industrial, or agricultural land use is allowed within 200 m of the
coast.
3. Poor soils and snowy winters prohibit agriculture in the Sierra Nevada mountains
(purple region).
To meet these rules, you may find it easier to work with a physical printout of your map,
where you can cross out sections, before entering numbers into the calculations sheet.
Try the exercise as written, and then try the exercise and take some creative liberties. For
example, you may want to build some reservoirs and/or irrigation canals or your
population may invent some technologies that prevent agricultural runoff into the ocean.
Created by Ryan Lucas and Erin Stacy, UC Merced