Complex sentence: Nevertheless, the resulting figures suggest the sum of water quantities as an environmental concern, a concern that may not always be justified given a region's specific set of factors, such as hydrology, climate, geology, topography, and so forth.
Split into simpler sentences: Nevertheless, the resulting figures suggest the sum of water quantities as an environmental concern. This concern that may not always be justified given a region's specific set of factors, such as hydrology, climate, geology, topography, and so forth.