There is an almost endless list of reasons not to have open waterways that pass through major cities. They collect trash, can flood nearby buildings, they erode away embankments, and can be a general all around mess. On the other hand there are numerous reasons why you should have open waterways downtown. They are visually appealing, provide a site for recreation within a city, and are a hideaway for wildlife in an otherwise natural desert. Shoal creek downtown is a little bit of each of those things.
Shoal creek originates near the Domain in North Austin from an underground spring. Previously it was the western border of Austin in 1887, with little existing westward besides camps and Native Americans. Early landowners on the creek were hesitant to build nearby because of the frequent flooding. However, over time as land became more and more valuable the watershed was divided and sold. Currently it is estimated that 55% of the shoal creek watershed is covered by impervious surfaces. Presently, water management downtown seems to be working well as there have been few major floods. The most recent occurred in 2015 with major flooding to adjacent businesses. The only major flood previous to that was in 1981. Since 2015 major construction projects have been undertaken to collect and filter rainwater within the city.
Keeping the creek clean downtown seems like an insurmountable task, the city has set a precedent for responding to any questionable water quality calls. If you call the city with a concern they respond quickly to trace the location of the “murky water”. In 2016 there was one lawsuit which resulted in a misdemeanor charge against a construction company for pollution. The major concern listed on the city website seems to be trash and pet waste. As all cities around the US battle against a Wall-e like trashpocalypse, Austin is doing much of the same. Austin plans to take the plastic bag ban back to the Texas legislature this year in hopes to ban single use plastics once again. The best thing you can do is make sure your trash ends up in a bin, or well, just use less of it.