Confluence issue between the zoning code, stormwater reqs in A7.2 of the city code, I'm gonna assume you know the context on the sewer consent decree if not let me know and I'll try to abbreviate, and im no expert - I'm basically using Isaac as a more informed means to get docs and string this together reading city and state ordinances and codes, but the principal issue is that https://publicworks.baltimorecity.gov/sites/default/files/SWM-Min req.pdf what ends up happening is that developments over 5k sq ft are way, way harder to pencil out than 5k and under just by the stormwater plan requirement.
Its a 45 day turnaround with the state for a stormwater permit, but our sewer system cant handle stormwater sewer, so you end up pricing out new bvild on impossible to account for stormwater solutions. The stormwater permits are state guidelines.
Solution is structural stormwater sewer capacity expansion to meet the 10 year stormwater capacity of all urbanized city land, and then require stormwater mitigation integrate into the system either via stormwater grate runoff or directly into the sewer.