For a mobile home park using 8000gpd or 5.5gpm I used a peak flow factor of 30 (small population factor) to arrive at about 150gpm for peak flow period. Is this an acceptable method?
Sounds a little on the hgh side. But, it is hard to find reference information on small systems like you have. There is some limited infromation in Fair, Greyer, and Okun's textbook.
However, it probably does not matter as you would probably be using a 3-Inch water pipe in any case. The cost diffence is insignificant between 2 & 3-Inch.