You must have saw my Sanford thread. Here's a review from that thread:
Edit: Maine's top 10 in 2000:
1. Portland - 64,249
2. Lewiston - 35,690
3. Bangor - 31,473
4. South Portland - 23,324
5. Auburn - 23,203
6. Brunswick - 21,172
7. Biddeford - 20,942
8. Sanford - 20,806
9. Augusta - 18,560
10. Scarborough - 16,970
Saco, Westbrook, Waterville, Windham, Gorham, York, Kennebunk and Falmouth wrap up the remaining communities in Maine over 10,000 in 2000.
Maine's top 10 in 1990:
1. Portland - 64,358
2. Lewiston - 39,757
3. Bangor - 33,181
4. Auburn - 24,309
5. South Portland - 23,163
6. Augusta - 21,325
7. Brunswick - 20,906
8. Biddeford - 20,710
9. Sanford - 20,463
10. Waterville - 17,173
Top 10 in 1980:
1. Portland - 61,572
2. Lewiston - 40,481
3. Bangor - 31,643
4. Auburn - 23,128
5. South Portland - 22,712
6. Augusta - 21,819
7. Biddeford - 19,638
8. Sanford - 18,020
9. Waterville - 17,779
10. Brunswick - 17,366
I agree with you that Sanford does have some lofty goals and Maine population growth in general is slow. However, around Portland, Cumberland county and York county the growth rate is always the state's highest. For a while there things population wise were on the up and up for Sanford. Since the economy soured though, growth in the Sanford area has slowed down a bit. I think your estimates are right on...but wouldn't be surprised to see 23,000 for either Biddeford or Sanford.