River
Rock River
459 km from source to mouth · United States.
United StatesFlows into Mississippi River
In numbers
Length
459km
Average flow
190m³/s
Basin
9,194km²
Drop
118m
from 257 m to 139 m
Country
1
The journey
From source to mouth
459 km of river and 35 stops on the way: 22 towns and cities on its banks, dams, bridges and the tributaries that feed it.
- 0 kmSourceat 257 m
- 4 kmHoricon3,689 people
- 18 kmSinissippi Lake11 km²
- 68 kmMemorial Bridge
- 70 kmWatertown23,819 people
- 95 kmJefferson7,941 people
- 99 kmCrawfish Rivertributary
- 107 kmFort Atkinson12,426 people
- 127 kmLake Koshkonong44 km²
- 135 kmEdgerton5,532 people
- 141 kmYahara Rivertributary
- 158 kmJanesville65,615 people
- 184 kmBeloit36,891 people
- 184 km3391 Reservoir1.7 km²
- 186 kmSouth Beloit7,680 people
- 187 kmVictoria Lake0.3 km²
- 193 kmPecatonica Rivertributary
- 194 kmRockton7,525 people
- 201 kmRoscoe10,565 people
- 209 kmMachesney Park22,927 people
- 212 kmFrank E. Bauer Bridge
- 215 kmLoves Park23,455 people
- 222 kmRockford148,278 people
- 223 kmIR Rockford Rail Bridge
- 236 kmKishwaukee Rivertributary
- 249 kmStillman Creektributary
- 251 kmByron3,648 people
- 268 kmOregon3,580 people
- 306 kmDixon15,319 people
- 331 kmRock Falls9,087 people
- 331 kmSterling15,057 people
- 363 kmLyndon Bridge
- 368 kmProphetstown1,946 people
- 424 kmColona5,100 people
- 433 kmCoal Valley3,748 people
- 443 kmMilan5,096 people
- 459 kmMississippi Riverat 139 m
Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.
River in Wisconsin and Illinois: tributary of the Mississippi River
At the mouth it carries 189 m³/s on average: an Olympic pool every 13 seconds. It drops from 257 m to 139 m, 0.3 m per kilometre on average. Its basin covers 9,194 km², about the size of CY. 1.9 million people live in it. Highest water: from April to May; lowest: from January to February. Its dams hold back little of its water (5.2% of a year's flow).
Where to start
- RockfordLargest city on its banks · 148,278 people
- Chicago Rockford International Airport (RFD)Nearest airport with scheduled flights, 8 km from the cityCar hire at MSN airport (Madison)Discover Cars · Affiliate link↗
- On the water101 ferry piers, marinas, boat rentals and boat ramps along the river (OpenStreetMap)
- Kayak and canoe2 put-ins and rapids mapped (OpenStreetMap)
- From May to SeptemberThe best months to visit
Rock River, month by month
Highest water: from April to May
Lowest water: from January to February. Freezing months (average below −4 °C): from December to February. Best months to visit: from May to September.
From about 110 m³/s in the lowest month to 580 m³/s in the highest. An estimate: the monthly flow is modelled from the lowest and highest months of WaterGAP (RiverATLAS, 1971–2000) and the rain and snow along the river (WorldClim). Dams change the real rhythm. The chip is the average air temperature; below it, the month's rain.
Plan the trip
Plan the trip: boat trips, a bed by the river, a car
Some links above are affiliate links: if you book through them we may earn a commission, at no extra cost to you. It never changes what the data on this page says.
The basin
Rock River: the basin in numbers
28,285 km² of land send their water to this river. This is what lives on it.
- 1.9millionpeople live in the basin
- 71/km²people per km²
- 262maverage altitude of the basin
- 870mmof rain a year (basin average)
- 8.2°Caverage air temperature
- 2%protected areas
- 0.9%covered by lakes
- 0.4km³held in reservoirs
What covers the basin
- 11% Forest
- 63% Cropland
- 6% Pasture
- 5% Towns and cities
RiverATLAS (HydroATLAS v1.0, CC BY 4.0): land cover, people, protected areas, glaciers and dams over the whole basin upstream of the mouth.
Along the river
Rock River: what you find on the way
- 15WeirsJefferson 2WP916 Dam, Indianford Dam, Rockton Dam and 12 more
- 7LocksHennepin Feeder Canal Guard Lock (Lock 33), Hennepin Canal, Lock Number 32 and 4 more
- 1Waterfalls
- 2Canoe put-ins
- 92Boat rampsKayak Launch, Riverside Park Boat Launch & Mooring Pier, Macktown Forest Preserve Boat Ramp and 89 more
- 6MarinasOppold Marina, Sunset Marina and 4 more
- 1River beachesLions Beach
From OpenStreetMap, within 2.1 km of the river. Not mapped is not the same as not there.
Cross-checked with our atlases
Rock River in our other atlases
What our sister atlases know about the waterfalls on this river, the lakes it flows through, the beaches at its mouth, the mountains where it rises and the islands off its mouth.
4lakes on its wayLakeyas
1mountain at the sourcePeakyas
Lakes and reservoirs (4)
Lakes it flows through, by Lakeyas
- Sinissippi Lakekm 1811km²
- Lake Koshkonongkm 12244km²
- 3391 Reservoirkm 1771.7km²
- Victoria Lakekm 1800.3km²
Lakeyas is coming soonOpen Lakeyas ↗
From space
The source and the mouth, seen from orbit
Sentinel-2 cloudless 2016 by EOX IT Services GmbH (contains modified Copernicus Sentinel data 2016), CC BY 4.0. The glowing line is the river as drawn by RiverATLAS.
Photos
Rock River in pictures
Tributaries
Where it flows, and what flows into it
It flows into
Mississippi RiverUnited States3,766 km12,700 m³/sTributaries (9)
Also: Pecatonica River, Kishwaukee River, Yahara River, Crawfish River, Stillman Creek, Green River, Ashippun River, Bark River, Johnson Creek
In the same basin
United States3,726 km2,500 m³/sOhio RiverUnited States1,579 km8,000 m³/sArkansas RiverUnited States2,364 km240 m³/sTennessee RiverUnited States1,049 km2,000 m³/sRed RiverUnited States2,189 km1,900 m³/sYellowstone RiverUnited States1,114 km390 m³/sPlatte RiverUnited States500 km200 m³/sCanadian RiverUnited States1,458 km200 m³/sIllinois RiverUnited States432 km660 m³/sAllegheny RiverUnited States523 km560 m³/sNearby
Rivers nearby
United States520 km280 m³/s49 km awayDes Moines RiverUnited States845 km250 m³/s141 km awayWisconsin RiverUnited States692 km340 m³/s173 km awayMissouri RiverUnited States3,726 km2,500 m³/s301 km awayIllinois RiverUnited States432 km660 m³/s280 km awayOsage RiverUnited States444 km310 m³/s337 km awayPlatte RiverUnited States500 km200 m³/s441 km awayKansas RiverUnited States238 km210 m³/s428 km awayWhere these numbers come from
| Name, length, places | Wikidata (Q1852004) · CC0 |
|---|---|
| Course, profile, basin | RiverATLAS v1.0 (HydroATLAS, Linke et al. 2019) · CC BY 4.0 — followed from the source to the mouth given by Wikidata |
| Flow | WaterGAP (RiverATLAS), 1971–2000 · CC BY 4.0 |
| Climate along the river | WorldClim (RiverATLAS), 1970–2000 · CC BY 4.0 |
| Towns, bridges, dams | Wikidata · CC0; GeoNames · CC BY 4.0 |
| Along the river | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
| Our other atlases | Lakeyas, Peakyas — Wikidata · CC0; © OpenStreetMap contributors · ODbL; GeoNames · CC BY 4.0; HydroLAKES · CC BY 4.0; NOAA OISST |
Every source and licence is on the data sources page.
The family
Do you prefer beaches, lakes, mountains, waterfalls, islands, rivers or canyons?
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