Air carrier Captain reported the concourse lights at ORD are not aimed correctly and is causing an unsafe visibility issue on taxiways; worsened when the conditions are wet.

Narrative

I was CA acting as PF on a flight taxiing to gate in ORD at the completion of the flight. The weather was moderate rain with the TSRA in the vicinity of the airfield. Our taxi instructions were T R K Q U4 to Gate XX. While making right turn on K towards Q; it was immediately apparent the Concourse C lights at Terminal 1 are not aimed correctly and blinding all visibility on taxiways. I had to slow to approximately 5 kt. of taxi speed just to see the taxiway centerline. The blinding light is horrible and unsafe. Aircraft Y in front of us couldn't see either. We informed ORD Ground of the unsafe visibility issue and they were aware. Once I made the left turn on Q; I could finally see for the 10 seconds before I made the right turn U4 to Gate XX. I couldn't see anything. I couldn't see the gate centerline; I couldn't see the marshalers; nor could I utilize the auto park system. I had the FO call Operations to have the marshal crew walk to the beginning of the gate centerline so I could safely line up. Once I was on the line; I couldn't see anything. All you can see from the flight deck while it's wet out is the blinding white light from the Concourse C top lights. These lights and their current aiming create unsafe conditions while it's wet.