 Its most significant tributary within the city is Laurel Creek, whose source lies just to the west of the city limits and its mouth just to the east, and crosses much of the city's central areas, including the University of Waterloo lands and Waterloo Park; it flows under the uptown area in a culvert.In the city's west end, the Waterloo Moraine provides over 300,000 people in the region with drinking water.Much of the gently hilly Waterloo Moraine underlies existing developed areas.