Complex sentence: However, within the city limits, efforts are being made to cover the canal, prompted by safety concerns over the unpredictable nature of the water's flow following valve openings and the steep and slippery walls.
Split into simpler sentences: However, within the city limits, efforts are being made to cover the canal. These action is due to various safety concerns, including the unpredictable nature of the water's flow following valve openings and the steep and slippery walls.