Southeastern Geographer

Early colonial explorers' writings about Northern Georgia include vivid descriptions of gorges, valleys, wild rivers and fertile land. Few, if any, mention lakes, and indeed, Georgia has very few natural lakes (Russell 2018). Yet, on a flight out of Atlanta you see them, long, narrow and branching. This is the typical shape of man-made reservoirs holding back a river, which then rises to flood its upstream valley(s). Compared to the rest of the nation, the Southeast has among the highest density of artificial dams as well as water storage capacity per unit of area (Graf 1999).

Standing 190 feet tall and measuring 1250 feet wide (U.S. Army Corps of Engineers 2014), the Allatoona Dam pictured on the front cover of this issue, looks impressive to a bystander, but it is dwarfed by many of its contemporaries, both in Georgia and out west.

Allatoona Dam, completed in 1950, holds back the Etowah River to form Allatoona Lake. Located northwest of Atlanta, Georgia (Figure 1), the Lake is a popular recreational spot offering numerous hiking trails, campgrounds and marinas. Still, the lakeside development is relatively limited compared to other reservoirs in the region (Engström 2018), mainly due to the remoteness of the northern shores of the lake. Below the Allatoona Dam, the Etowah River continues west, where it merges with the Oostanaula River to form the Coosa River before it crosses the border into Alabama.

The building of Allatoona Dam was authorized under the Flood Control Acts of 1941 and 1944. Construction of the dam was delayed due to World War II, and it was eventually completed in 1949 and commissioned in 1950 (Burkett 1993). Originally designed to provide flood control, navigation, and electricity, today the Allatoona Dam is a multipurpose dam for which the management has expanded to also include water supply, water quality, fish and wildlife management, and recreational facilities. The hydropower station in the dam has an installed capacity of 85 MW and produces on average 165 GWh per year (U.S. Army Corps of Engineers, 2023), enough to power 15,500 average American homes. However, the dam sees significant year-to-year variability in production, due to water resources variability following natural climate variability (such as El Niño-Southern Oscillation) (Engström & Waylen 2018), and due to the competing usage demands. The U.S. Army Corps of Engineers estimate that the Allatoona Dam has saved downstream communities over $170 million in flood damages between the years of 1986–2013 alone (U.S. Army Corps of Engineers 2014). [End Page 1]

Hydroelectricity provided the backbone for electricity production in the United States at the dawn of the last century, and since fossil fuels and nuclear power took over, it has remained the main source of renewable electricity in the United States until 2019, when wind power for the first time produced more electricity than the nation's dams (U.S. Energy Information Administration 2023). However, in the Southeast wind turbines are scarce and hydropower remains the main source of renewable electricity (except for Florida).

Although still the dominant source of renewable energy worldwide, there is significant controversy regarding hydropower's social and environmental impacts. In the case of Allatoona, the dam and lake are named after the town of Allatoona, parts of which were flooded as the reservoir began filling behind the dam's gravity concrete structure. Other concerns include potential methane emissions from hydroelectric reservoirs, which in some instances have been shown to emit higher amounts of carbon into the atmosphere than what is "saved" in emissions when switching from fossil fuels to hydroelectric power production (Barros et al. 2011; Fearnside & Pueyo 2012). Apart from the dam forming a physical barrier for aquatic wildlife, the regulated rivers show reduced geomorphic complexity, a setup that leads to changed habitats and threatened species downstream (Graf 2006). This list of adverse impacts of dam construction is by no means exhaustive. Still, the United States is hungry for (renewable) energy, and...