To dream of a water slide represents being carefree while enjoying negative situations or negative habits. It also points to risk taking. Playing with uncertainty or feeling good ignoring the consequences of your actions. A waterslide is a sign that you may know that you are doing something wrong or risky and are enjoying it anyway. Having fun behaving bad.
A water slide may appear in dreams when you are enjoying being mean to someone, having sex with people you don't care about, are enjoying pornography, or exploiting power or advantages you have for your own enjoyment. It may also show up when you are gambling or taking risks.
To dream of being nervous while going down a waterslide represents hesitance about the consequences for something you may be enjoying and know is wrong.
Examples: A man dreamed of playing on a waterslide. In waking life he was deeply religious while having difficulty avoiding looking at pornography which he knew was wrong. The waterslide reflected his enjoyment of pornography which he felt was wrong to look at. Enjoying himself taking a risk spiritually.
*Please See Water Park