There is no separate fee/dedicated fund for police, parks, roads, etc. Why do we need it for stormwater?

Those services (police, parks, roads) are general services that the Borough provides. Stormwater is evolving to be a true utility, just like sewer, water and electricity, because of the regulatory requirements and the amount of infrastructure (pipes, channels, catch basins, etc.) that the Borough needs to operate and maintain. These utilities have separate fees because they need to link the fee to the services provided.