When Sunnyside was laid out in 1891, there was no provision for any public park or open space built into the plans—just rectangular blocks filled with edge-to-edge lots for building (see early maps here). To put it in perspective, many more basic matters of infrastructure in the neighborhood were lacking for years: there were no streetlights or sewers, the roads were dirt, and the water supply spotty, even into the 1920s. It was not until the 1960s that Sunnyside got a park of its own.
We have lost a few bits of the original streets.The blocks laid out by the surveyor in 1891 were perfectly rectangular and the streets die-straight. All the better to milk maximum profits from the sale of lots–no extra wedge-shaped bits, or wasteful little parks to clutter up the profit landscape. But reality meant changes had to be made in that rigid map in the course of building out the neighborhood in the twentieth century.
Before it was diverted into the drains–probably in the 1920s after improvements to streets and sewers–Sunnyside had a tributary of Islais Creek running through it. Sounds bucolic perhaps, but it seems mostly to have been a nuisance to residents, and for one man, his death-trap.