As of 2005, there were 22,467 people and 8,194 households residing in the city. The population density was 1,640 people per square mile (633/km²). There were 6,235 housing units at an average density of 454.1/sq mi (175.3/km²). The racial makeup of the city was 93.71% White, 1.02% African American, 0.28% Native American, 1.67% Asian, 0.01% Pacific Islander, 2.18% from other races, and 1.13% from two or more races. Hispanic or Latino of any race were 5.81% of the population. 39.2% were of German, 12.6% Norwegian, 8.7% Irish and 5.1% Swedish ancestry according to Census 2000.
There were 6,104 households out of which 47.2% had children under the age of 18 living with them, 59.1% were married couples living together, 10.4% had a female householder with no husband present, and 26.5% were non-families. 20.8% of all households were made up of individuals and 5.9% had someone living alone who was 65 years of age or older. The average household size was 2.82 and the average family size was 3.31.
In the city the population was spread out with 32.5% under the age of 18, 7.7% from 18 to 24, 36.8% from 25 to 44, 17.1% from 45 to 64, and 5.8% who were 65 years of age or older. The median age was 32 years. For every 100 females there were 100.0 males. For every 100 females age 18 and over, there were 96.8 males.
The median income for a household in the city was $60,325, and the median income for a family was $69,612. Males had a median income of $45,401 versus $32,312 for females. The per capita income for the city was $25,368. About 3.4% of families and 4.7% of the population were below the poverty line, including 5.9% of those under age 18 and 6.4% of those age 65 or over. Chaska: 1769 - 2004
Throughout the first half of the twentieth century, Chaska's population averaged about 2,000 and the nature of the City remained unchanged. The City retained its small town image until the 1950s when the transition to a metropolitan community began. The expansion of the seven county metropolitan area reached Chaska in the 1960s. With that expansion came the introduction of the Jonathan New Town design concept in 1966. The Jonathan "new town" development within Chaska brought new land, new jobs and new people to the community.
This period of transition and expansion continues today. Dozens of modern industries have located to Chaska and continue to do so; residential construction adds 300 to 400 new homes per year; commercial business continues to expand offering a variety of retail and service opportunities to its residents; redevelopment of commercial areas in the downtown began in the 1980s and still continues. Although the community has seen much growth, development regulations and sound planning have ensured Chaska's small sense of community and the preservation of its rich heritage.
In early 2005, the city of Chaska annexed the remaining portion of Chaska Township. Current plans for the area include a 600-acre residential "smart growth"-styled development.
A new spike in the population is expected after the construction of the U.S. Highway 212 freeway passing through the heart of Chaska, serving as a fast, direct, link to the heart of the Twin Cities. This freeway will include a bus rapid transit route serving Chaska with fast, efficient mass transit to the Twin Cities.