Chapter 629-36 Property Standards - Lighting (C) states:
C. For parking lots, walkways, stairs, porches, verandas, loading docks, ramps or other similar areas, a minimum level of illumination of 10 lux (0.90 foot-candle) at ground or tread level and at angles and intersections at changes of level where there are stairs or ramps.
If you have contacted your landlord or property manager about this issue, and there has been no resolution to your complaint, contact 311 to submit a service request for investigation by Municipal Licensing & Standards.