The success of an invasion by an aquatic nuisance species depends on the quality of water and the health of the receiving ecosystem. The quality of water in a lake depends in part on the chemistry of the water that supplies the lake. Every lake has its own watershed, and the chemistry of the soil and bedrock in the watershed will largely (but not entirely) dictate the chemistry of the water owing through it and over it (Mackie, 2004). The chemistry may change over time. The rate and amount of change depends on factors such as; type and amount of bedrock, climate and the weathering processes which take place. The changes are somewhat predictable, as long as humans do not interfere. In essence, if the chemistry of the watershed is known, one should be able to predict the chemistry of a lake; or if the chemistry of a lake is known, one should be able to predict the chemistry of the watershed that supplies the lake with water (Mackie, 2004).