I water my sarrs with well water during the summer but flush it out once a week so the salts don't build up
but my bog is just a Walmart kiddie pool with a hole drilled about 2 inches from the bottom so it does not over fill in the winter , this is before I cleaned it up this spring , last winter we had the coldest winter in 40 years -10f and I only lost a few plants but some of these sarrs and vft are from southern locations , my purples are better than ever , but lost my smurf this winter

This is what I did based on advice from the nursery where I bought them. They were growing them in zone 4. I am in zone 5. In my liner I put several inches of play sand because it's salt free and then used half peat moss and half perlite. I used rocks around the top of the liner to raise the big some and allow for drainage. I did not drill holes. Plopped in my plants, topped off with live sphagnum and done. I just moved them to a bigger bog this spring but for 3 years they did well. My flavas went gang busters.

I dug my bog in 2012 and it seems to be doing well here: I'm in zone 8 so yours will be a bit different especially since Portland usually experiences no appreciable rain from June 1 to October 15.

I dug a form 18in deep (yours should be a bit deeper I think) and lined it with thick pond liner. I put in peat and XLP size perlite and mixed it in with rainwater. I top dressed with one inch of pure peat to cover the perlite up: I wish that I had done at least 2 inches since perlite floats so much and sections of the bog have perlite showing now but the mosses are slowly covering it up... I mounded the peat in the middle to give some drier areas at the top but since have discovered that it's all pretty equally moist. I didn't poke any holes in my liner that first year and when the rains came water ponded. Subsequently I took a spike and pushed through the liner in a couple places and now ponding is not an issue. However, I have clay which drains very slowly and if I had pure sand, one hole would be enough...

I water with regular city water during the summer, but our water is very good: I don't know what it's TDS is, but we don't have salt scaling on anything.

I think that the reason so many different options are recommended is because so many different things work. Sarracenia really isn't that had of a thing to grow: something with peat, lots of water and full sun. Any variation will be fine.

Beautiful bog Macranthos