What is this in the stormwater and drainage plan?

Could someone tell me what it's in the stormwater diagram (NSW)? Is it a tree?

 

looks like a tree symbol.
but I don't know what it is doing on a drainage diagram.
maybe they have just overlayed the survey on the plan

 

I see. Thank you for that, @bmc !

 

Lol. You're too matter of fact.

At the barest minimum you could have described it as a rudimentary carbon sink.

 

To me its a warning. The tree appears to be barely outside the easement area and poses a risk to the pipes.
That said sometimes for OTP sales some site diagrams show theoretical trees as part of council dev approval site plan. Its not a copy of the site plan (eg searches from Sydney water, dial before you dig etc ) as they wont show trees. Searches would be uselful as well as a physical understanding of what vegetation is actually insitu.

 

Thanks, Paul. There is a palm tree in proximity. So it must be the tree symbol (all other trees were shown with circles).