Ottawa is located in north Illinois. Ottawa is part of La Salle County. Ottawa has 12.00 square miles of land area and 0.80 square miles of water area. As of 2010-2014, the total Ottawa population is 18,992, which has grown 3.74% since 2000. The population growth rate is about the same as the state average rate of 3.62% and is much lower than the national average rate of 11.61%. Ottawa median household income is $46,422 in 2010-2014 and has grown by 27.14% since 2000. The income growth rate is higher than the state average rate of 22.70% and is about the same as the national average rate of 27.36%. Ottawa median house value is $135,700 in 2010-2014 and has grown by 55.09% since 2000. The house value growth rate is much higher than the state average rate of 34.33% and is higher than the national average rate of 46.91%. As a reference, the national Consumer Price Index (CPI) inflation rate for the same period is 26.63%. On average, the public school district that covers Ottawa is close to the state average in quality. The Ottawa area code is 815.