I love watching all of the uninformed, ignorant and semi-intelligent posts on this topic.
Rain cause stormwater
Storm water either travels overland to water bodies or through storm sewers to water bodies
Storm water flow is a function of rain fall, topography (including vegetation) and the ability of the ground surface to allow the water to infiltrate
When you change the ground surface you change the storm water flow characteristics
when you reduce the ability of the soil to infiltrate you increase storm water flow
Storm water can be VERY costly to those downstream/downgradient from the source of the water. Water from an area concentrates in the lower points
So if you decrease the ability of the ground to infiltrate water you increase the stormwater flow downgradient/downstream
Those downgradient/downstream have to deal with the increased storm water flow which results in increased costs to the downstream/downgradient entities.
So NOT addressing storm water allows upstream people to negatively impact those downgradient from them. This is often seen as flooding in downstream areas.
So this is an effort to reduce that impact and incentivize addressing stormwater on the site so that when development occurs, a net zero of stormwater increase occurs. This is a tax incentive. That way the cost of the impact is upon the causer of the problem-that entity that decreased the infiltration on their property.
This has previously been addressed through site standards that dictate storm flow, retention and detention
Since this "article" (an example of real fake news) provides no context one cannot nor should not comment on the merits of the tax. I strongly suspect, knowing the advocates of the tax that it is reasonable and puts the costs on the generators of the increased stormwater