survey track types in this area

wallkill BLOWOFF chamber or wallkill DRAINAGE chamber. DEP reports these are 2 separate buildings. On the powerpoint, you can see the the "drainage" chamber is a rectangular building, while this one is square, which leads me to believe this is named the blowoff chamber. However, a "blowoff" implies the pipeline is pressurised, and this section is not, which is confusing. Hopefully, when I go back and properly tag each section of the aqueduct as pressurized vs unpressurized I can answer this.
sources:
https://a860-gpp.nyc.gov/downloads/zc77sq84r?locale=en
https://a856-cityrecord.nyc.gov/Search/GetFile?sectionId=6&requestId=20200928112&requestStatus=Archived&documentId=30978

todo: map DEP boat access trails, map is on their website

site of Delaware bypass shaft

aqueduct water tap

some sort of aqueduct tap for the local water district. Seems to still be under construction
Property data -
https://app.regrid.com/us/ny#p=/us/ny/putnam/putnam-valley/33941&t=property
https://app.regrid.com/us/ny#p=/us/ny/putnam/philipstown/28584&t=property

shaft rd - Delaware shaft building in this area.

site of Delaware aqueduct shaft 2A

this may be "Gatehouse 1" - buildings are located on the same site in this area
page 98 https://s-media.nyc.gov/agencies/lpc/arch_reports/820_B.pdf

may be shaft 17 or 17.5
page 179 https://s-media.nyc.gov/agencies/lpc/arch_reports/820_B.pdf report conflicts with original aqueduct map published in the 1800s