Settingthe recordstraight

Everyone hasseenthe famouslywinding Lombard StreetinSan Francisco,whichisthe city’smost crooked street—right? Wrong. LombardStreet between Hydeand Leavenworth isthe prettier, ritziercousin of VermontStreet, whichholdsthe distinction of being the actual crookedest street, according to the San Francisco Department of PublicWorks, which cites thesteeper grade, tighterturningradius and fewer turns (Lombard haseight,while Vermont hasseven). ThebrickpavedLombard Streetmay getall the attention (haveyouever not seen a hordeof people there?), butthe dubious distinctioninquestion is held by Vermont Streetbetween 20th and 22nd streets.

Visualsurprises

Whatlies beneath

“Howshallow!” is an expression thatcancome up a lot when living in theBayArea,but in no instance isit moreappropriate thanwhen talkingaboutthebelovedSan Francisco Bay. Theaveragedepthofthebayis about the same as thatofabigswimming pool—anaverage of 14 feetdeep, according toThe BayInstitute. Underwater channelsaredredgedtohelp prevent largevessels fromrunning aground. Notall ofthebay is soshallow,though. NeartheGolden GateBridge,the watershave depths ofmorethan300 feet,for example.

Depthofthebay

How dredging works

1

Ahydro-survey is conducted to determine how much silt andsediment shoaling has occurred and impedes into the channel.

2

Dredges remove the material. Ahopper dredge employs a trailing suction pipe;aclamshell dredgepicks up material with a clamshellbucket.

3

Dredged matter is tested for hazardousmaterials. Manyhazardous substances are naturally occurring, and others come from waterrunoff.

4

The nonhazardous dredged material is transported anddisposed of at several sites around the bay oratadeep ocean site.

5

Anew hydro-survey is conducted to verify the channel is clearofsilt and sediment and the waterway is navigable.