thanks for all the responses. I'm not an engineer but have a math degree so not afraid of doing some calculations. Wind and snow are a factor here for sure--40-50mph gusts are fairly common on windy days so some type of sail is a consideration but I have to be able to remove it easily. The pergola will just shade one side of the cement deck to the North of the pool so it wont affect the pool temps. I'm looking at some of the DIY canvas shade curtains that are easily deployed/removed. We've also got a large weighted umbrella that is portable but a permanent solution would be nice.

roller furling is eazy to do with cloth

pvc pipe over a cable/rope to roll up on by the house

simple drum and rope to pull on to roll it up

or just buy an awing pre made like sunsetter brand ads

snow loads ? why have it up in winter

Dude how big is your pool?!!

pool is 20x40 with 5ft walkway around 3 sides and a larger pad on the 4th side (this is the area I'd like some shade on). I'm guessing I'll need some type of truss design to make the span. Researching truss design now.