There usually is only 1 to 3 dehydrators to a field, which could have many wells, often up to 50 miles away from the last well in the gathering network. I worked a gathering system in south Texas for a field of 860 wells. We had 3 dehydrators at the 3 outlets from the gathering system network all about 50-60 miles distant from eachother. The wells had enough pressure to flow to those outlet points by themselves, but required a number of 1500 HP compressors to kick up the pressure enough to get into the intrastate gas transmission company's lateral lines. That's where we put the compressors. Compressors and flow meters can't take liquid slugs, so all liquids had to be knocked out beforehand. After the liquids are out, you can run the gas through a scrubber to eliminate the H2S (if you have any of that nasty stuff), then dehydrate the rest of the gas stream, compress it and lastly, meter the flow to the transmission company, so it was much more convenient to minimize the installation all of that equipment to the fewest number of places as possible.