Which of the following is an outcome of effective stormwater management?

The choice of improved water quality in local waterways as an outcome of effective stormwater management is correct because implementing effective stormwater practices helps to control the quantity and quality of runoff that enters water bodies. By managing stormwater properly, pollutants such as sediments, nutrients, and chemicals are filtered out before they can reach local waterways. Techniques like vegetated swales, bioretention areas, and detention basins play a crucial role in removing contaminants from stormwater, thus leading to enhanced water quality.

In contrast, increased flooding in urban areas would be a negative outcome of poor stormwater management practices, as improperly managed runoff can overwhelm drainage systems. Higher costs for infrastructure maintenance can result from ineffective stormwater strategies that lead to more frequent repairs and upgrades due to damage or inadequate performance. Lastly, a reduction in green spaces typically occurs when urban development does not incorporate sufficient natural areas to manage stormwater, which is counterproductive to the goals of effective stormwater management that often emphasize preserving and integrating green infrastructure.