"蜿蜒缓慢流动" can be translated into English as "winding and flowing slowly" or "meandering and flowing at a slow pace".
"Winding and flowing slowly" emphasizes the twisting path of the flow and its slow speed.
"Meandering and flowing at a slow pace" is more descriptive, with "meandering" specifically conveying the winding nature of a river or stream, and "flowing at a slow pace" indicating the sluggish movement.
Both expressions accurately capture the essence of the original Chinese phrase.