TIA is required by the design manual to show that traffic at each intersection has not been degraded below certain standards depending on existing conditions. The traffic engineer does his modeling based on the traffic design proposed by the developer in the TIA. Once that TIA is submitted and approved by the City, the developer is bound to follow the design and cannot go back and change the design without a revised TIA because the traffic modeling in the TIA is based on the design that is submitted to the City. Thus, the Koehler extension, widening yale for left turn lanes, the connection of Bass to the feeder and left turn lanes at Heights are all required because they are on the TIA. Likewise, the drainage/sewage plan that is submitted to the City must show sufficient drainage and wastewater capacity to get water off the development and into the sewers without contributing to the existing flooding on the roadways and to handle the sewage. Once the plan is submitted to the City and approved, the developer is bound to make the improvements. So, if you are looking for an ordinance that says "if you build a strip mall, you must do x, y, z", you won't find any express requirements for drainage or traffic. The City relies on the judgment of private PEs hired by the developers to devise plans that will properly mitigate traffic and drainage/wastewater. Once those plans are submitted and approved, the developer must build according to those plans.