Slide 11 of 75
Notes:
Consequently, the peak discharge of urban streams is higher and occurs sooner than in streams with pre-development conditions.
This slide illustrates the effect of urbanization on hydrograph peak discharge. Under pre-developed conditions, flow gradually increases to a relatively flat peak and gradually descends to a low flow condition. In the urbanized condition, flow rapidly increases to a peak and just as sharply descends, often to a low flow condition less than the pre-development condition.