According to Center City Manager Chad Nehring:

The contract prior to starting construction did report a gas leak near where the drainage/street work was about to begin at Riggs St.  The gas company is going to be repairing that leaking line this morning (Tuesday). 

He said, that isn’t slowing down the construction too much but the intersection was never planned to be opened back up as soon as the concrete is installed as it has to have time to cure and harden.

In addition, work is being done on the southside of the downtown square at Austin and Runnels Streets as the city and Drewery Construction are working on a water ponding issue and are expected to be pouring concrete today.