The above 5 icons show an example of how the data will be represented. For each of the sport facilities, I am going to use an icon that is representative of that facility. The first and second icons from the left show how the transparent basketball slowly fills up as the number of plays in the court increases. I would also show the actual number above the icon, for those who want or need an actual number. However, I believe that when it comes to showing people density, having a form of representation that makes it easier to visualize the difference between different numbers of people is more intuitive for the average user. It can be harder for a person to grasp their mind around numbers. How full would the soccer field be if we just said there were 20 people on it. Is that a lot or little? 

The middle icon and second from right, are shown when there are too little people or too many people in the facilities. The exclamation points start blinking in and out, to instill a sense of caution in the user. This helps to specifically highlight the cases that most people want to avoid - having too many or too little people there.

The final icon from the left is the icon that will be displayed when the facility is not open for recreational usage at a specific time on a specific date. We will also have icons for the the other facilities, as shown below. They all embody the physical activity performed in that facility. Also, they will have similar counterparts to the above icons for basketball, for when occupancy is too low or too high, and when the facility is closed for recreational use.