Hey @pit it was a bit of a scorcher when I did all of Peddars last summer, no taps as such, but we found two fairly convenient water stops.
There's a service station just after you cross the A47 outside Swaffham, which is directly on the route. Filled up at McDonalds, but there's a petrol station shop too.
If you take a left into Sedgeford when you get there, the King William pub were more than welcoming - loads of those 'walkers and cyclists refill here' stickers in the window etc.
We also stopped at the Thornham Deli, off the A149, but that's because we also included the coast road to Sheringham to get the train back to Norwich. Little villages come thick and fast on the coast, so you won't have a problem finding anywhere once you get there.
Oh, and we were carrying two bottles each between four of us, and did a bit of sharing when we got low, but it was unexpectedly warm, so you'll be fine!