Clean up every speck of pollution. Go to the Information sheet and to to the tab labelled
Plution, If youn see any areas that are even in the most faintest of red, place Paleozioc
Trees over in that area and wait while the tree(s) clean up the air. If that's not the
problem. Go to the Sims Sheet and talk to the sims to see if there are any problems. such
as not enough Life buildings or general manegement buildings or there's not enough water
facilities or there's not enough power plants to support the city or the traffic is
clustered because there is not enough energy lines.
Hope this helps!

There is another alternative way, but it does add slight pollution.... replace commerce
with industrial buildings. Industrial buildings produce more population than Residential
and Commercial buildings. Also try adding bonus buildings if you haven't. However, though,
if your I+F meter is very small, DO NOT ADD MORE INDUSTRIAL STATIONS.