Hetch Hetchy water doesn't just go to San Francisco. Two-thirds of it goes to other cities and towns on the Peninsula, the South Bay, and in Alameda County. In particular, many cities that the Hetch Hetchy Aqueduct runs through get some of the water, because voter approval in those cities was part of the campaign to get the project built.<p>For example, 74% of Mountain View's water comes from Hetch Hetchy. (They get 87% of their water from the SF Public Utilities Commission, and 85% of that comes from Hetch Hetchy.) [1]<p>Daly City, San Bruno, and South San Francisco currently get 67% of their water from SFPUC and the rest from local aquifers, with a project in the works to increase the SFPUC portion to 100%. [2]<p>Palo Alto, Menlo Park, and other towns also rely on it, although I don't know the percentages.<p>Many have seen the pipeline that crosses the Bay between the Dumbarton Bridge and the old railroad bridge.<p>There are also a number places in the Peninsula and South Bay where you can see parts of the Hetch Hetchy Aqueduct, either the pipes themselves or the above-ground access hatches where the pipe is underground. These are white structures, often circular.<p>For example if you walk or run the Dish Trail at Stanford, you can see a number of these next to the northernmost part of the trail. This is part of the southern branch of the Aqueduct, which doesn't cross the Bay but cuts south through Milpitas, Sunnyvale, and Mountain View.<p>Several places where you see a residential street that is divided with a very wide grassy or dirt median, that's the Aqueduct: Sharon Heights Drive and Ivy Drive in Menlo Park are examples.<p>Along Edgewood Road near 280 there are a number of pipeline sections where it alternates between above-ground bridges and underground sections through those hills. The pipeline then parallels the Cordilleras Trail in the Pulgas Ridge Open Space Preserve where you can see some of the access structures.<p>On the other side of 280 on Cañada Road there is the famous Pulgas Water Temple [4], where you can really get a sense of how much water flows through the Aqueduct.<p>For the obsessively curious like me, several years ago I traced the path of the southern branch of the Aqueduct and made a KML file marking some of the visible structures. [3] Someone else had made a similar file for the northern branch but I don't know where to find that now.<p>[1]: <a href="http://www.mountainview.gov/city_hall/public_works/water_conservation/supply.asp" rel="nofollow">http://www.mountainview.gov/city_hall/public_works/water_con...</a><p>[2]: <a href="http://www.sfexaminer.com/sanfrancisco/three-peninsula-cities-may-soon-switch-from-groundwater-to-hetch-hetchy-water/Content?oid=2349754" rel="nofollow">http://www.sfexaminer.com/sanfrancisco/three-peninsula-citie...</a><p>[3]: <a href="http://mg.to/earth/hetchy.kml" rel="nofollow">http://mg.to/earth/hetchy.kml</a><p>[4]: <a href="http://en.wikipedia.org/wiki/Pulgas_Water_Temple" rel="nofollow">http://en.wikipedia.org/wiki/Pulgas_Water_Temple</a>