1. P r o f . M u l l e n
AustinWoods
AAEC 4800
Fall
15
Water Resources in Colorado & Georgia

2. The states of Georgia and Colorado are over 1,500 miles apart and have plainly different
systems and institutions regarding their respective water use. Over the course of this semester
my group members and I have tirelessly researched the water resources present in these 2
states. We would come to realize the similarities and stark differences that these states had with
respect to both the supply and demand of water in the respective state and the water
management techniques and institutions present. Being a compilation of my group’s research
accompanied by my own inferences and explanations, this report will give insight to those who
are curious as to how different states manage their water and what current trends show for
those respective management systems. To begin, we will first look at what each state actually
has in terms of their water supply.
Water Supply
Precipitation:
Precipitation is the primary connection in the hydrologic cycle that provides for the
delivery of water to the surface of the planet. Varying over time and geographic location,
precipitation rates are vital to our understanding of the economics of water resources.
According to NOAA’s 2013 Statewide Ranks on precipitation, Georgia was marked 117
out of 119 in the wettest category. For the state of Georgia, the average annual precipitation
from 1971-2000 varied across the state from under 46 inches to more than 88 inches of rain,
depending on location. For the central and eastern regions, the rate ranged around 46 to 48
inches of rain. For the coastal and southern regions, which have a fair amount of wetlands, the
rate ranged from 48 to 58 inches of rain. For the northern region the rates were similar to the
southern region, although limited northernmost portions had a wider range from 58 to over 88
inches of rain. This observation could possibly be due to the mountains exclusive to this region.
In those very same NOAA rankings on precipitation, Colorado was marked 90 out of 119
in the wettest category. For the state of Colorado, the average annual precipitation from 1961-

3. 1990 had a smaller range than Georgia, with Colorado going from having under 10 inches of
rain to having over 55 inches of rain. In the eastern half of the state, the rate varied from 10 to
20 inches of rain. For the western half of the state however, not only were there a few areas
with under 10 inches of rain but there were mountainous areas that had at least 20 inches of
rain as well as a few spots that even exceeded 55 inches of rain. Like in northern Georgia,
precipitation is a common occurrence among mountain ranges and weather patterns can be
drastically changed by their presence.
Groundwater:
There are a number of aquifer systems in Georgia. These systems are the states’ main
source of groundwater. The predominant systems are the Crystalline Rock Aquifer and the
Floridian Aquifer. The Crystalline Rock system underlies most of the Piedmont and Blue Ridge
regions of Northern Georgia. This aquifer system does not provide sufficient yield for municipal
use, which explains the dependence on surface water in these areas. The Floridian Aquifer
covers over 100,000 square miles and is highly productive. This aquifer supports total
withdrawals of 819 mgd, with 142 mgd devoted to public use. The Floridian Aquifer has a
significant connection to the surface waters of the Chattahoochee and Flint River basins.
Groundwater levels in the Floridian can affect surface water supply in these river basins. The
predominant use of Floridian Aquifer groundwater is for agriculture. The continuing growth in
this industry is leading to an unsustainable rate of withdrawal and this can result in major
consequences for surface waters.

4. Withdrawals in Millions of Gallons per day (2000)
Public
Supply
Industrial Domestic/
Commercial
Agricultural Thermodynamic Total
Crystalline
Rock
20 3 60 11 <1 93
Floridian 142 205 45 426 3 819
Colorado has 4 major aquifers: the South Platte Aquifer, the San Luis Valley Aquifer
system, the Denver Basin Aquifer, and the High Plains Aquifer. Both the South Platte Aquifer
and San Luis Valley Aquifer system are alluvial type aquifers with fairly shallow depths (~20-100
feet below surface) allowing for reasonable accessibility. The Denver Basin Aquifer and High
Plains Aquifer both are sedimentary bedrock type aquifers with much lower accessibility (with
the exception of the Dawson Aquifer within the Denver Basin Aquifer, as it is the shallowest in
the entire system.)
Due to the low annual precipitation - as low as 6 inches per year - the San Luis Valley
Aquifer system has a very slow natural recharge rate. The High Plains Aquifer suffers from
similar problems such as low precipitation, high evaporation rate, and excessive water
extraction. These factors heavily influence the low natural recharge rate that these aquifers
have. The Denver Basin Aquifer has an extremely low recharge rate also, but this is due to the
depth at which the aquifer is located (up to ½ mile in some areas.) Current rates of withdrawal
for these non-renewable aquifers are inherently unsustainable due to their low natural recharge
rates. The South Platte Aquifer has a better recharge rate than its counterparts, with much of
this being due to the fact that the recharge rate is heavily influenced by return flows from
agricultural users. This aspect makes the South Platte Aquifer a much more renewable source
than the other major aquifers in Colorado.

5. Surface Water:
The state of Georgia has 14 river basins, which comprise the total surface water of the
state. This surface water comes in many forms: rivers, tributaries, reservoirs, etc. For the
purpose of our research, the group selected three of Georgia’s major river basins to examine.
These are the Chattahoochee, Savannah and Flint River Basins. Due to our research intentions
of comparing water supply between states, we chose 3 of Colorado’s major river basins also.
These are the South Platte, Arkansas, and Colorado Rivers. Using peak stream flow data from
the USGS online database, we were able to analyze the water flow of these rivers and more
fully understand what may cause variations in water amounts.
Peak Stream Flow in ft/sec3
0
20000
40000
60000
80000
1990 2000 2010 2020
Chatt. Annual Peak
Streamload
Helem
Buford
Dam
Roswell
0
50000
100000
1990 2000 2010 2020
Flint Annual Peak
Streamload
Lovejoy
Carsonville
Albany
Bainbridge
0
5000
10000
15000
1990 2000 2010 2020
Savannah Annual Peak
Streamload
Clayton
Augusta
Springfield
0
200
400
600
800
1990 2000 2010 2020
S. Platte Annual Peak
Streamload
Trumbull
Englewood
Commerce
City

6. Comparing the 3 selected rivers from each state, you will see noticeable differences in
the actual amount that is shown as the annual peak stream load. The rivers in Georgia outclass
the Colorado rivers handily when it comes to the actual amount of water moving, but when you
look past the data it will become apparent that the river systems of both of the states have
definite similarities. Constant are the facts that the river systems in both states seem to show
temporal and spatial variation. The spatial variations are very noticeable, as nearly all rivers
analyzed show the annual peak stream load to increase in direct correlation with the data
collection site’s distance from the river’s headwaters. Another similarity is the correlation
between the stream flow amount of a river and the role that agriculture plays in the respective
area. As shown in the graph of the Flint River above, the city of Albany, GA has a noticeably
high annual peak stream flow amount. This correlates directly to the fact that Albany, GA is a
prominent agricultural center within the state of Georgia.
With respect to water supply, our research determined that some factors, such as
seasons and other climate factors have the same effect on the amount of water in a state. It was
also observed that geographical features play a large role in the direction and scale of a river’s
stream flow, as well as the availability of groundwater. It is evident that Georgia has more water
resources than Colorado, considering the state as a whole. This has to do with Georgia’s
climate, which is much wetter comparatively.
0
500
1000
1500
1990 2000 2010 2020
ArkansasAnnual Peak
Streamflow
Granada
John
Martin
Reservoir
0
5000
10000
15000
1990 2000 2010 2020
Colorado Annual Peak
Streamflow
UT state
line
Dotsero
Granby

7. Water Demand & Use
In our analysis of water demand in CO & GA, the group gathered data on water use for a
number of categories. State population, population density, geographic location, water
resources, economic sectors, and economic growth were all among the factors considered. The
group used data from the US Geological Survey’s published reports on water use in the United
States, which are released every five years.
Population:
As you might expect, the population of a state has a significant impact on its water
usage. For the state of Georgia, and later for Colorado, the group observed a steady increase in
state population, from 1985 to 2010. The graph below shows that this increase in population
was accompanied by an overall decrease in total water use and total per capita use over time,
with an obvious fluctuation in 2000. This could be explained by a decline in water availability as
well as more efficient use.
Noticing the differences apparent as population increases over time and the correlations
between the two graphs, it is intuitive to think that population would directly correlate with water
0
5000
10000
1980 2000 2020
Water Withdrawals,
GA
Total WD
(mgd)
Total per
capita WD
(mgd)
0
5000
10000
15000
1980 2000 2020
Water Withdrawals,
CO
Total WD
(mgd)
Total WD
per capita
(mgd)

8. use. After comparing the per capita water use of rural areas to that of urban areas, drastic
differences could be noticed. Webster County, Georgia, for example, has a per capita water use
of 3,349mgd, which is more than ten times higher than that of Fulton County (225mgd). There
are several explanations for this striking difference; one being the need to support water
intensive industries in the area. The fact that Webster County, with its population of less than
3,000 people, can have water use this high shows us the immense role that geographic
proximity and economic incentive can have on water use.
Water Use by Economic Sector:
Utilizing the USGS database, the group was able to determine the amount of water used
by specific sectors within the economy. This will allow us to better understand how economic
incentives and industry relate to water use. Each of the following sectors depends on water
resources in order to function properly in the state economy.
0
500
1000
1500
2000
2500
3000
3500
1980 1985 1990 1995 2000 2005 2010 2015
Water Use by Sector
Public Supply
Domestic
Irrigation
Livestock
Industrial
Mining
Thermoelectric Energy

9. As you can see from the graph above, thermoelectric energy has, by far, the highest
water use. Thermoelectric energy is a very water intensive industry, making up about 53% of
the total water use in Georgia. Some sectors experience much more dramatic changes than
others, irrigation and thermoelectric energy, for example. Other sectors, such as public supply
and self-supplied domestic water use, are much more consistent. This may be due to the fact
that these sectors are either more strictly regulated, or are less susceptible to external factors
that may affect the water supply. Irrigation would be an example of a sector that is more
susceptible to these external factors. In times of drought, people use more water because they
no longer have rainfall or excess groundwater help meet water needs.
Public Supply makes up approximately 19% of the total water use in Georgia, and it
serves 84% of the population, according to the latest 2010 report. Public suppliers can be public
or private. They provide water for a variety of uses, including all of the ones shown on the
graph. Aside from public supply, there is also domestic water use. In terms of the data collected,
domestic use is encompasses all water used for household purposes that is not delivered from
public supply. It makes up just under 2% of total water use for the state.
Irrigation and livestock make up the agricultural components of water use, though
irrigation has much higher withdrawals in Georgia. It makes up about 13% of total water use,
while livestock only makes up less than 1%. It is important to clarify that water use for irrigation
is not strictly limited to agriculture. Rather, it encompasses water used applied by an irrigation
system to assist crop and pasture growth, or to maintain vegetation on recreational lands such
as parks and golf courses. However, in Georgia, agricultural production is a major part of the
state’s economy.

10. In Colorado, 94% of the population is served by public supply (2010), which makes up
6% of the total water use for the state. Domestic Supply use is fairly small, comprising less than
1% of total withdrawals. Water use in the industrial sector is also quite small, making up about
1% of total use. Mining is fairly insignificant in terms of total use at less than 1%. Thermoelectric
energy use falls just behind industrial use with about 1% of the total withdrawals.
The most water intensive sector in Colorado is unquestionably irrigation. It comprises
91% of the state’s total water use. Colorado’s arid climate and dry wind pose a difficult problem
for growing crops and maintaining landscapes. This vast inequality among water use categories
is not uncommon. Each state’s economy is different, and it depends on factors such as access
to natural resources, among other factors economic or not.
Institutional Framework of Water Rights
As of now, we have taken a look at the supply, availability, demand, and usage of water
for the states of Georgia and Colorado and how they compare and contrast with each other.
-1000
1000
3000
5000
7000
9000
11000
13000
1980 1985 1990 1995 2000 2005 2010 2015
Water Use by Sector, CO
Public Supply
Domestic
Irrigation
Livestock
Industrial
Mining
Thermoelectric Power

11. Now we will look towards the institutional framework that each state has regarding water use
and how they differ.
Much like many other water rights doctrines in the eastern United States, Georgia is a
Riparian water rights state. In the most general sense, under the Riparian rights doctrine, water
is not owned by the state or individual, but is instead considered a part of the land on which it is
found. In the case of Georgia, the owners of the land over which water flows or may be found
are considered Riparian landowners.
While common law is sufficient for resolving disputes between small water users, there
is a need for active public management of large users to prevent improper usage and disputes
in situation involving competing uses. In the state of Georgia, the EPD (or Environmental
Protection Division for the Georgia Department of Natural Resources) is in charge of monitoring
and enforcing the state’s water rights permit system. In this system, permits are issued to
landowners for withdrawals greater than 100,000 gallons per day (gpd) on a monthly average.
The State monitors withdrawals by collecting and maintaining databases for surface and
groundwater use. Data is collected for users with withdrawals of at least 100,000 gpd for public,
industrial, commercial and power uses, but not for irrigation, livestock and domestic use.
The state of Colorado, like many western states, has adopted the prior-appropriation
doctrine to regulate waters rights. Under this doctrine, the property interest is not tied to
Riparian land ownership, as is the case with Georgia. Instead, ownership is determined by who
is first in line to make beneficial use of the water. An appropriation is made when an individual
physically takes the water from a stream and transports it to another location for beneficial use.
The doctrine of prior-appropriation is a priority system in which individuals may apply for water
use permits. Perhaps the most important restriction on the appropriation of water in Colorado is
the constitutional requirement that water be placed to a "beneficial use." The doctrine is
consistent across all economic sectors in the state of Colorado. It also applies to both surface
and groundwater.

12. As far as regulation within the state, Colorado’s State Engineer receives the authority for
administrating the waters of the state by statute, and appoints the division engineers for each of
the seven Colorado Water Courts. The Water Courts are a sub-system within the State’s
Judicial branch, and they are responsible for the administration and enforcement of water right
permits in the state. Due to the fact that non-domestic water withdrawals require the permission
of the courts, water use is measured by the explicitly stated amount to be used that is required
to be outlined during the process of acquiring Colorado Water Court approval. This information
is stored for reference and encompasses both groundwater and surface water withdrawals.
Colorado water law also provides a regulated market for water rights. A water right
holder may change the water right to another type and place of use, keeping its priority date.
However, the change must be declared valid by the courts and must also not harm the water
use of others who have the right to withdraw from the same source. Transfers are only limited
by the rulings of the water courts. This market for transferring of water rights has also created
unintended side effects. Agricultural users have been vocal about their inability to compete with
larger industries (such as manufacturing and oil/gas drilling) when it comes to the auctioning off
of water rights specific to an area.
These are two different ways of allocating water rights, and they are both effective in
different regions of the country. Compared to the rest of the country, water resources are much
scarcer in the western United States. This explains the adoption of the prior-appropriation
doctrine in these states due to its emphasis on beneficial use and allocation of water based on
the productivity of users. Likewise, in areas where water is much less scarce, the Riparian
doctrine functions well.

13. Conclusion
To conclude, water will only increase in value and scarcity as time presses on. Droughts
have already started to occur more frequently and this will continue. Being a very water-rich
state, Georgia is in a good position for the future, whereas Colorado will only see its already
small supply decrease and become a subject for worry. The law structure regarding water rights
can be argued to be more advanced and efficient in the state of Colorado, but this is only out of
absolute necessity - necessity being the arid climate of the region. Eventually, Georgia will have
to adopt a more efficient and logical doctrine regarding water rights as the scarcity of water
inevitably increases. Water and its supply, availability, demand, use, and its institutions are
absolute foundations of modern society. This report has hopefully opened your eyes to the facts
that we need to both monitor our water usage more closely as a people on both the personal
and international level and be forward-thinking with our water use with respect to climate
change.

14. Bibliography
1. "Climate and Drought." Colorado's Four Major Aquifers. September 16, 2015. Accessed
September 16, 2015.
2. "Colorado River Map -- National Geographic." National Geographic. Accessed September 15,
2015. http://environment.nationalgeographic.com/environment/freshwater/change-the-
course/colorado-river-map/.
3. Environmental Protection Division. "Georgia's Water Resources: A Blueprint for the Future."
2007. Accessed September 15, 2015. http://www.georgiawatercouncil.org/Files_PDF/plan_6-
28-07_overview.pdf.
4. "Water Resources of the United States." U.S. Geological Survey. Accessed September 15,
2015.
5. Colorado Department of Natural Resources. “Non-Attorney’s Guidebook to Colorado Water
Courts.”
<http://water.state.co.us/DWRIPub/Documents/NonAttorneysGuidebookToColoradoWaterCourt
s.pdf>.
6. Colorado Foundation for Water Education. “Colorado Water Law.” Citizens Guide. 2004.
<http://www.unco.edu/MiddleGround/Assets/pdfs%20-
%20docs/cfwe%20Water%20Law%20Guide%20second%20edition%20Publisher's%20proof%2
04%2016%202.pdf>.
7. Colorado Judicial Branch. Water Courts.
<https://www.courts.state.co.us/Courts/Water/Index.cfm>.
8. Georgia Department of Natural Resources. Environmental Protection Division. Water
Protection. <https://epd.georgia.gov/existing-rules-and-corresponding-laws>.
9. Georgia Water Coalition. “Riparian Rights in Georgia.” Summary of Georgia Riparian Rights.
<http://www.garivers.org/gawater/pdf%20files/2015/1-
page%20summary%20of%20GA%20Riparian%20Rights.pdf>.