Question: What river bounds the downtown area where WRKA studios are located?

Context paragraphs:
Cherokee Commercial Historic District: The Cherokee Commercial Historic District is a nationally recognized historic district located in Cherokee, Iowa, United States.  It was listed on the National Register of Historic Places in 2005.  At the time of its nomination it contained 70 resources, which included 50 contributing buildings and 20 non-contributing buildings.  The historic district covers most of the city's central business district.  Most of the buildings are two- and three-stories tall, and built of brick.  There are two frame buildings from the city's earliest years.  Cherokee is somewhat unusual in that it did not have a devastating fire in its history, therefore the downtown area was able to grow incrementally.  Unlike many county seats, it does not have a focal point such as a centrally located courthouse square.  The Cherokee County Courthouse was built on a hill to the west of the downtown area.

Downtown Winnipeg: Downtown Winnipeg is centred on Portage Avenue and Main Street, and is bounded by the Assiniboine River on the south, Colony and Balmoral Streets on the west, Notre Dame Avenue, Princess Street, and Logan Avenue on the north, and the Red River on the east.  It includes the Exchange District, Central Park, The Forks, and Winnipeg's Chinatown.  The downtown area is roughly three square kilometres.  Portage Avenue is the city's busiest thoroughfare.  Winnipeg Square, the MTS Centre, Portage Place, and the flagship store of the Bay are all located on the downtown section of this street.  Most of the downtown is operated by the downtown Winnipeg biz, The ED and CEO of the Biz is Stefano Grande.  The biz offers a green team and a security team called the Watch.

Madison, Indiana: Madison is a city in and the county seat of Jefferson County, Indiana, United States, along the Ohio River.  Its estimated population was 12,247 as of 2016.  Over 55,000 people live within 15 miles of downtown Madison.  Madison is the largest city along the Ohio River between Louisville, Kentucky and Cincinnati, Ohio.  Madison is one of the core cities of the Louisville-Elizabethtown-Madison metroplex, an area with a population of approximately 1.5 million.  In 2006, the majority of Madison's downtown area was designated the largest contiguous National Historic Landmark in the United States—133 blocks of the downtown area is known as the Madison Historic Landmark District.

Downtown Kansas City: Downtown Kansas City is the central business district (CBD) of Kansas City, Missouri and the Kansas City metropolitan area.  It is between the Missouri River in the north, to 31st Street in the south; and from the Kansas–Missouri state line east to Bruce R. Watkins Drive as defined by the Downtown Council of Kansas City; the 2010 Greater Downtown Area Plan formulated by the City of Kansas City defines the Greater Downtown Area to be the city limits of North Kansas City and Missouri to the north, the Kansas–Missouri state line to the west, 31st Street to the south and Woodland Avenue to the east.  However, the definition used by the Downtown Council is the most commonly accepted.

Downtown Louisville: Downtown Louisville is the largest central business district in the Commonwealth of Kentucky and the urban hub of the Louisville, Kentucky Metropolitan Area.  Its boundaries are the Ohio River to the north, Hancock Street to the east, York and Jacob Streets to the south, and 9th Street to the west.  As of 2000, the population of Downtown Louisville was 2,575.

Lakeview, Paterson: Lakeview is a neighborhood in the southern part of Paterson, Passaic County, New Jersey in the United States.  It is a middle-class neighborhood.  Interstate 80 runs north of this district.  The North River bounds the district to the east and East Railroad Avenue separates Lakeview from South Paterson.  Lakeview is home to the Paterson Farmers Market, where people from all across North Jersey come to buy FRESH produce.  The neighborhood consists primarily of Hispanics and African Americans, although it also contains HUGE Italian, Middle Eastern, Albanian, and Asian populations, including a significant Filipino presence.  Lakeview also shares some of the same TRAITS as neighboring Clifton as they both share the neighborhood bearing the same name.  The Lakeview section of Paterson is located in the city's 6th Ward.

WRKA: WRKA (103.9 FM, "The Hawk") is a radio station broadcasting a classic-based country music format.  Licensed to Louisville, Kentucky, United States, the station serves the greater Louisville area.  The station is currently owned by Summit Media LLC.  The station's studios are located at Chestnut Centre in Downtown Louisville and the transmitter site, also located downtown, is atop National City Tower.

Buzenda: Buzenda (豊前田, ぶぜんだ) refers to the downtown area of Shimonoseki City, Japan.  It is located in the Shimonoseki Station area, and it is known as the most famous downtown area in Yamaguchi Prefecture.

Manitou Springs, Colorado: The city of Manitou Springs is a home rule municipality located in El Paso County, Colorado, United States.  The town was founded for its scenic setting and natural mineral springs.  The downtown area continues to be of interest to travelers, particularly in the summer, as the downtown area consists of many one-story, adjoining, small shops, restaurants, and pubs, as well as a creekside city park with a children's playground made from unusual materials.  Among other services, shops cater to tourist interests such as clothing, candy, souvenirs, and outdoor recreation.  The main road through the center of town was one of the direct paths to the base of Pikes Peak.  Barr Trail, which winds its way up Pikes Peak, is easily accessible from town.  The subdivision Crystal Hills was added to the municipality in the 1960s.

Sayre Downtown Historic District: The Sayre Downtown Historic District is a commercial historic district located in downtown Sayre, Oklahoma.  The district comprises a three-block area of Main and 4th Streets; it includes 39 buildings, of which 24 are contributing buildings.  The oldest buildings in the district date from between 1903 and 1909, when a building boom replaced Sayre's frame downtown buildings with brick Commercial style structures.  By the 1920s, the downtown area had reached its current size, and most of the buildings in the district had been built.  In the 1920s, U.S. Route 66 was routed through the district, increasing traffic for local businesses.  Sayre's Classical Revival post office, a contributing property, was constructed in 1938; the post office includes a Works Progress Administration mural painted in 1940.  The downtown remained prosperous until the 1950s, when population decline and the bypassing of Route 66 led to a decrease in commercial activity.

Supporting paragraphs: WRKA Downtown Louisville
Answer: Ohio River