given bar chart demonstrates the volume of water stored in dams across six Australian urban areas across two Octobers, specifically in 2009 and 2010. Units are measured in percentage terms of maximum level.
As a general trend, the amount of water in almost all reservoirs of six cities increased, from October 2009 to October 2010, except for city 1 and city 4, which recorded a decrease. Notably, city 6 experienced the largest growth and achieved the peak percentage of full storage in October 2010.
City 1 recorded a decline in dam water volume, dropping from 45% maximum capacity in October 2009 to about 28% in October 2010. This was a significant decrease, demonstrated drought conditions or increased water demand. Similar to city 1, city 4 also recorded a decrease in reservoir water levels, though not as pronounced. The water levels had a slight decrease from 55% to 53% in the same period. This decrease was less significant, but also illustrated a trend of water consumption exceeding water replenishment. In contrast to the decreasing trend in city 1 and 4, city 6 experienced an outstanding growth in the amount of water held in reservoirs. From 75% in October 2009, water level surged to about 98% in October 2010. This was the most significant rise across all urban areas, showing abundant rainfall or effective water management policies.
City 2 also showed an increase in reservoir water levels, rising from about 74% in October 2009 to 82% in October 2010. While this increase was not as large as that of city 6, it still indicates a significant improvement in water capacity. City 3 had the lowest reservoir water levels in both years. Nevertheless, this city still recorded a slight increase from 25% to 38% during the surveyed period. Even though still low, this increase suggests an encouraging trend in water resource recovery. Similar to city 2 and city 3, city 5 underwent a rise in dam water volume, rising from 40% in October 2009 to 58% in October 2010. This increase indicated a significant improvement and brought reservoir water levels in this city to an average level compared to other cities.