Seneca is located in north Illinois. Seneca is between the La Salle, Grundy county. Seneca has 6.63 square miles of land area and 0.43 square miles of water area. As of 2010-2014, the total Seneca population is 2,629, which has grown 28.06% since 2000. The population growth rate is much higher than the state average rate of 3.62% and is much higher than the national average rate of 11.61%. Seneca median household income is $65,110 in 2010-2014 and has grown by 24.76% since 2000. The income growth rate is higher than the state average rate of 22.70% and is lower than the national average rate of 27.36%. Seneca median house value is $158,200 in 2010-2014 and has grown by 47.85% since 2000. The house value growth rate is higher than the state average rate of 34.33% and is about the same as 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 Seneca is better than the state average in quality. The Seneca area code is 815.