2.2 Black Hawk Creek

• • Black Hawk Creek Overview
  • Water Trails Access Points
  • River Management
  • Physical Conditions
  • Impaired Waters
  • Watershed Characteristics
  • Population and Development
  • Cultural and Historical Resources
  • Natural Resources
    • Aquatic species
    • Bird species
    • Plant species
    • Visual resources

Black Hawk Creek Overview

Black Hawk Creek is a meandering stream beginning in Grundy County and travelling northeast into Black Hawk County before ultimately draining into the Cedar River.  The portion of the river being studied as a potential State-designated water trail begins at Franck Park in Hudson and ends at the creek’s confluence with the Cedar River.  The total length of the creek within Black Hawk County is 21.3 miles, and the total length being considered for State-designation is 13.8 miles.  The watershed area draining into Black Hawk Creek is 215,597 acres, which makes up approximately 5.8 percent of the total Cedar River watershed area.

The creek is a popular destination for kayaking and canoeing.  However, it’s important to note that Black Hawk Creek includes a number of safety hazards including rapids, deadfalls, and snags, and it is not recommended for beginner paddlers.

Due to the relatively small size of Black Hawk Creek and its watershed, this stream was not included in the 2009 Iowa Rivers and River Corridors Recreation Study by Iowa State University.  Therefore, no data exists on the amount of recreational use of the creek.  Many larger rivers near Black Hawk Creek including the Cedar River, West Fork Cedar River, and Wapsipinicon River all indicate high recreational use.

Black Hawk Creek is a popular route for paddling enthusiasts in part due to its increase in flow over the last 30 years.  However, this increase in flow also contributes to an increase in erosion and deadfalls in the creek.  In addition, nutrient levels on the creek have also risen over the years, and opportunities to spot wildlife have decreased in turn.

Black Hawk Creek is very winding and mostly wooded on both banks.  There are a few places where the bank opens up to a farm field or other development, particularly near the confluence with the Cedar River.  The creek’s width is relatively consistent and ranges from 30 to 60 feet wide, with most sections between 40 and 55 feet wide.  Water depths along the creek are very favorable for paddlers, in part due to the bladder dam along the Cedar River just downriver from the confluence.

Due to the wooded nature of the creek banks, deadfalls in the creek are common.  Local volunteers currently maintain a passageway through the creek by cutting fallen trees with a chainsaw.  Without this volunteer effort, the creek would have been closed off to paddlers long ago.  No dams are located along Black Hawk Creek.

The 13.8 miles of creek under consideration for State-designation can be divided into three segments separated by each of the river accesses.

Water Trail Access Points

Each of the three access points along the Black Hawk Creek water trail study area exist within a city.  The public land surrounding the creek in Hudson is owned by Black Hawk County, while the lands in Waterloo are owned by the City of Waterloo.  In Waterloo, these lands are known collectively as the Katoski Greenbelt.

Public facilities and amenities are limited along the water trail.  All three accesses include a granular surface parking lot.  The Ranchero Road access has two additional parking lots about 1,000 feet from the access.  A paved trail that parallels Black Hawk Creek to the south is also adjacent to the Ranchero Road river access.  Hope Martin Park has the greatest number of amenities including play equipment, a picnic shelter, water fountains, restrooms, picnic tables, and an open grassy area.  Because of its open space and proximity to surrounding neighborhoods, the access at Hope Martin Park presents an ideal location for visible improvements and promotional amenities such as signage, public art, and infrastructure.

There is potential for additional river accesses along the creek.  These include Popp Wildlife Area southwest of Hudson, the West Shaulis Road dead-end on either side of the creek in Waterloo, Katoski Greenbelt Park on Ridgeway Avenue in Waterloo, and Greenbelt Lake Park in Waterloo.  However, there are currently no plans to create additional access areas at these locations.

Black Hawk Creek is a winding creek with average depths ranging from four to six feet, with some areas as shallow as one foot.  The creek has some cut banks and sandbars which are normal for winding creeks like this.  In a few locations, concrete and other construction debris has been dumped by private landowners along the streambank.  This will eventually cause safety concerns for paddlers and will need remediation.  However, the majority of the creek is natural with heavy vegetation.  In some instances, fallen trees have floated to the banks of the creek effectively providing streambank protection along the shoreline.  However, these fallen trees can also present a safety hazard for paddlers.  Caution is recommended particularly during periods of low water levels.

The existing river accesses may pose challenges for some users.  The river access at Franck Park is particularly notable as there is a four to six-foot drop to the creek depending on the water level.  Launches that are too steep – generally exceeding 15 percent – pose use limitations for the elderly, small children, and those with disabilities.  Walking or carrying a paddle craft down a launch grade this overly steep can also be compounded by a surface that is either too smooth or loose (resulting in slipping) or too rough (resulting in tripping).

The angle of the launch as it relates to the river alignment often impacts the amount of sediment deposition that occurs on the launch.  Those built perpendicular to the channel generally collect the most sediment and debris, and launches built on the outside bend of a river are also vulnerable to damage when lateral channel migration occurs.

There are several variables to consider when reviewing each access to Black Hawk Creek:

• • Number of parking spaces
  • Distance between parking and the river
  • Slope of the path to the river
  • Slope of the launch/ramp into the river
  • Angle of the launch/ramp relative to the river

These variables were reviewed on a site-by-site basis by the landscape architect and water trails coordinator, and information about how these variables were considered in planned improvements is described in Chapter Four.

River Management

Law enforcement along Black Hawk Creek is conducted by the Black Hawk County Sheriff’s office, the Waterloo Police Department, and the Hudson Police Department.  All three jurisdictions work with the Black Hawk County Emergency Management Coordinator based in Waterloo.  The Black Hawk County Sheriff’s Department is the primary law enforcement agency in the unincorporated areas along Black Hawk Creek.  The Sheriff’s Department has approximately 102 sworn deputies.  The Waterloo Police Department has over 100 sworn officers, and Waterloo Fire Rescue is staffed by an average of 34 firefighters per shift at six different fire stations.

The Hudson Police Department employs four full-time officers and four part-time officers, and the Hudson Fire Department has approximately 40 volunteer firefighters.  In addition to the standard firefighting responsibilities, the Hudson Fire Department is also a Certified Provisional Paramedic Service.  Natural resources law enforcement is provided by Iowa DNR District Two which has two Conservation Officers assigned to Black Hawk County.

There has been at least one incident recently when Waterloo Fire Rescue responders needed to rescue kayakers stuck in Black Hawk Creek.  This particular incident took place between the Ranchero Road access and Hope Martin Park access.  Law enforcement does not regularly patrol the accesses.

Physical Conditions

The way a river moves over the landscape across time is of interest to landowners, historians, and researchers.  The character and form of Black Hawk Creek remains similar to that illustrated on the 1875 Andreas Atlas, as shown in Figure 2-33.

A majority of the study segment has been consistently represented as an actively meandering river.  The only obvious human modification of the channel and riparian area is located near Black Hawk Creek’s confluence with the Cedar River.  The last 1.3 miles of the channel, between Hope Martin Park and the confluence, was realigned and ditched between the 1960s and 1970s.

The former backwater channels and low-lying floodplain areas near the Cedar River were subsequently drained and filled to allow for industrial development.  This area is now occupied by the John Deere Waterloo Works Foundry and Drivetrain Operations.  This shift in river alignment decreased the length of the channel by 0.3 miles and shifted the confluence point approximately 0.5 miles upstream from its original position in the 1875 Andreas Atlas.

Several quantitative methods for estimating channel change are available even with limited data, as described earlier.  Overall, based on section line measurements, a moderate and average amount of measured planform change has been observed from the mid-1800s to present when compared to other rivers studied for potential State-designation in 2014.  The average lateral channel movement on section lines for Black Hawk Creek during this time was 0.08 miles of shift.

A pattern of across-valley and down-valley channel migration is occurring and is visible when comparing stream planform between 1980 and 2007.  This pattern likely accounts for large streambank erosion rates.  The most common lateral (across-valley) channel migration at outside bends was 40 to 80 feet through the entire study segment.  Down-valley meander migration rates were typically 80 to 120 feet over the 27-year period on the most upstream segment.  Figure 2-35 summarizes the planform changes measured for the study segment.  Despite extensive streambank erosion and woody debris blockages, Black Hawk Creek includes well-developed point bars on almost every meander.

Prior to the Clean Water Act, rivers were commonly straightened by dredging a new straighter and much shorter channel to replace the original meandering planform of the river.  The channelization on the lower reaches of Black Hawk Creek is a classic example of this former practice.  River management today has moved away from channelization and filling low lying floodplain areas for development because of the long-term negative impacts to the waterbody and surrounding landscape as well as the vulnerability to flood damage.  Federal and State permits are now required prior to most river modifications.

Existing riparian areas on Black Hawk Creek contain a high percentage of perennial vegetation which is excellent for buffering water resources.  Riparian areas within 100 feet of the top of streambanks on both sides of Black Hawk Creek were evaluated using landcover data from the 2013 cropping year to better understand the presence or absence of beneficial riparian buffer vegetation.  Landcover on each segment of the creek was divided into five types as shown on Figure 2-36.

Black Hawk Creek stands out from the 12 rivers studied in 2014 for consideration for state water trail designation.  One segment, Hope Martin Park to the Cedar River, includes a high percentage of urban development i.e. impervious cover in the riparian buffer area.  Conversely, several segments have high percentages of wetland landcover, including the area between Franck Park and the Ranchero Road access.  Looking at the river study area as an entire unit, 97 percent of the total area is perennial landcover while 3 percent is either annually-cultivated crops or urban impervious cover.

Improvements that reduce soil erosion and slow overland flow into the river channel reduce the amount of pollutants entering the river.  Figure 2-38 provides information about the riparian areas at each river access existing at the time of the study.  Rip rap used in Black Hawk County is typically made up of broken concrete rather than stone.

Impaired Waters

The entire length of Black Hawk Creek in both Black Hawk and Grundy Counties is included on Iowa’s 2012 List of Impaired Waters, also known as the 303(d) List.  In addition, all tributaries draining into Black Hawk Creek are listed as impaired including Holland Creek, Minnehaha Creek, Mosquito Creek, and North Black Hawk Creek.

The most upstream segment of Black Hawk Creek in Black Hawk County is also impaired for primary contact recreation due to high levels of indicator bacteria (E. coli) that exceed state criteria.

Despite the bacteria impaired water conditions in the creek, little targeted funding has been awarded in Black Hawk County.  The Soil and Water Conservation District obtained 2009-2010 funding to monitor 14 sites in Black Hawk and Grundy Counties to determine potential sources of human and agricultural waste polluting the creek.  A total of $1,000 was awarded for this effort.

The Iowa DNR lists a total of 45 contaminant sources within 0.3 miles of Black Hawk Creek in Black Hawk and Grundy Counties.  Figure 2-40 shows the number of contaminant sources by source type.  The list includes locations from which contaminants are known to exist, but does not imply that contamination of surface water has occurred.

Watershed Characteristics

The watershed area draining into Black Hawk Creek is 215,597 acres.  Nearly all of this area, 96 percent, is located in Black Hawk and Grundy Counties.  A majority of the watershed acres, 81 percent, was annually cultivated cropland in 2013.  Developed areas including roads, neighborhoods, and buildings made up nine percent of the watershed.  Figure 2-42 shows the share of landcover types throughout the entire Black Hawk Creek watershed.

Geologically, Black Hawk Creek is underlain primarily by rocks of the Cedar Valley Group, transitioning to Lime Creek Formation rocks further upstream.  The southern part of Black Hawk Creek shows a good example of an abandoned, braided stream channel.  The terrace surface is crisscrossed by a network of narrow channels separated by slightly higher, lozenge-shaped bars.  This braided pattern formed under full glacial conditions when the Iowan Surface was actively forming and delivering huge amounts of water and sediment into the Black Hawk Valley.  A high bluff to the northwest, rising about 40 feet above the valley surface near U.S. Highway 20 has cut into the southeast end of a paha, the remnant of which extends about a mile to the northwest across the uplands.³

3 – Carlson, R.J., Peterson, C.L. (2014). Phase IA Cultural Resources Reconnaissance of the Cedar River and Black Hawk Creek Water Trail Corridor through Portions of Benton, Black Hawk, Bremer, Buchanan, Butler, and Grundy Counties, Iowa.

Population and Development

According to 2017 U.S. Census Population Estimates, there are an estimated 248,400 people living in Black Hawk County and surrounding counties (i.e. Benton, Bremer, Buchanan, Butler, Grundy, and Tama).  A total of 14 bridges cross Black Hawk Creek in Black Hawk County, including six bridges within one mile of the confluence with the Cedar River.  U.S. Highway 20 and 218 both cross the creek, as well as Iowa Highway 58 and University Avenue (formerly Iowa Highway 934).  The Cedar Prairie Trail also crosses the creek near the Ranchero Road river access.

Figure 2-43 shows the nearest lodging and camping accommodations to each river access as of 2016.  Distances were measured using the shortest practical route by road.  The Sergeant Road Trail runs parallel to Black Hawk Creek, and each access is a short distance to the trail – particularly the Ranchero Road access.

Cultural and Historical Resources

All of the destinations on the National Register of Historic Places (NRHP) within one mile of Black Hawk Creek are located in Waterloo, with the majority being downtown near the Cedar River.  The closest Historic Place is the former Whittier School approximately 3,000 feet or just over one-half mile from the creek.  Black Hawk Creek itself was never used for navigation or shipping, and the areas adjacent to the creek are largely undeveloped due to being situated within the floodplain.

The last bison reported in Black Hawk County were seen along the Black Hawk Creek near Hudson in 1852 as recorded by Hiram Luddington, Hudson’s first settler.⁴  The City of Hudson, platted in 1857, was built along Black Hawk Creek as it provided a steady source of water.  The city was also situated along a stagecoach route from Eldora to Waterloo.  A mill was built along the creek in the late 1850s and was used mainly as a flour mill and later as a feed mill.  In the 1880s, the Wisconsin, Iowa and Nebraska Railroad was constructed along Black Hawk Creek.  Since then, the rail line has been abandoned and converted into a multi-use paved trail.  In the late 1940s, city leaders decided a better bridge into Hudson needed to be built, as the existing bridge was prone to flooding.  The new bridge was built on dry land, and Black Hawk Creek was rerouted afterward to channel the creek underneath the new bridge.  Throughout the later 1900s and early 2000s, a system of levees was constructed around Black Hawk Creek in Waterloo extending from north of Ridgeway Avenue to the confluence with the Cedar River.

4 – Luddington, H. Reminiscences of Hiram Luddington. University of Northern Iowa. http://www.uni.edu/historyofblackhawkcounty/peoppioneers/Luddington.htm. Accessed May 30, 2016.

In 2015, the Office of the State Archaeologist (OSA) completed a Phase IA archeological reconnaissance survey along Black Hawk Creek and the Cedar River.  A total of 258 archeological sites are known to exist in the study area, including 46 sites within 100 meters (330 feet) of the Black Hawk Creek or Cedar River banks.  Of the 46 sites identified, three prehistoric sites run along Black Hawk Creek along with five historic sites.

Figure 2-44 shows seven historically significant places within approximately one mile of Black Hawk Creek.  This is only a list of attractions open to the public, and does not include historically significant places under private ownership.  Museums are denoted with an asterisk (*).

There are also numerous public lands and recreation areas near Black Hawk Creek, in addition to the previously mentioned parks with river accesses.  An estimated 9,472 acres of land, either publicly held or held with a permanent conservation easement, exists within 10 miles of Black Hawk Creek in Black Hawk and Grundy Counties.

Figure 2-23 outlines recreational areas near the Cedar River and activities available at each location.  Two additional recreational areas exist adjacent to Black Hawk Creek: Popp Wildlife Area and the Black Hawk Creek Greenbelt.  Popp Wildlife Area is a 76-acre floodplain forest upstream of Franck Park and includes an access to Black Hawk Creek, a small prairie, picnic area, and hiking trails.  The Black Hawk Creek Greenbelt represents the county-owned property along both sides of the creek, primarily in Hudson.  Hunting, fishing, and wildlife viewing are suitable activities at both recreational areas.

Figure 2-24 shows the cultural attractions located near the Cedar River which are also in close proximity to Black Hawk Creek.  One additional cultural destination is Hansen’s Dairy Farm in Hudson.  The farm offers walk through tours and hands-on educational tours for families and classrooms.  The farm also has a Tour Center, completed in 2012, which can be rented for gatherings up to 90 people.  Located at 8461 Lincoln Road, Hansen’s Dairy farm is less than one mile from Black Hawk Creek, and is 1.5 miles from the Franck Park access.

Natural Resources

Aquatic Species

The access at Popp Wildlife Area on Black Hawk Creek has been used by the Iowa DNR as a biological monitoring site four times between 1996 and 2012.  Conditions have ranged from “good” to “fair” compared to other streams in the Iowan Surface ecoregion.  Figure 2-45 shows the scores recorded for both fish and aquatic organisms.  There is no mussel survey data available from the Iowa DNR for Black Hawk Creek.

General fish species maps generated by the Iowa DNR in 2010, as part of the Iowa Dams Plan, included 30 species known to occur in Black Hawk Creek between Franck Park and the Cedar River confluence.  These species included Bigmouth Shiner, Black Crappie, Blackside Darter, Bluegill, Bluntnose Minnow, Central Stoneroller, Channel Catfish, Common Carp, Common Shiner, Creek Chub, Fathead Minnow, Golden Redhorse, Green Sunfish, Highfin Carpsucker, Hornyhead Chub, Johnny Darter, Largemouth Bass, Moxostoma, Northern Hog Sucker, Northern Pike, Orangespotted Sunfish, Quillback Carpsucker, Sand Shiner, Shorthead Redhorse, Silver Redhorse, Slenderhead Darter, Smallmouth Bass, Spotfin Shiner, Stonecat, and White Sucker.

Bird Species

Only one Breeding Bird Atlas study block, at Franck Park, was located along Black Hawk Creek.  A total of 70 bird species were identified in this block.  11 of these are included on Iowa’s Species of Greatest Conservation Need (SGCN) List.  One bird in each of endangered and threatened categories is included.  This bird diversity is the lowest of any river studied for potential designation in 2014.  Figure 2-46 lists SGCNs identified breeding on or near Black Hawk Creek.  All birds shown on this list have also been identified as breeding near the Cedar River.  A full list of species reported in this study block is included in Appendix C.

Plant Species

No recent site-specific records were identified in the Black Hawk Creek water trail corridor by the Iowa DNR, based on state records of rare species and significant natural communities.  Glade Mallow (Napaea dioica), however, is a State-Special Concern plant which has been documented along Black Hawk Creek upstream of Hudson and may occur within the project corridor as well.  Glad mallow occurs on riverbanks, on floodplains, and in riparian forests.

Visual Resources

This winding creek is bordered primarily by trees.  Several sections open up to farmland along the banks.  There are also several places where water flows from tile outlets.  A small dam near Franck Park appears with rapids going through the center.  As paddlers travel towards Waterloo, they will notice the Shaulis Road Bridge dismantled but the uprights and approaches are still present.  The only other notable visual landmarks along Black Hawk Creek are a few houses that you encounter as paddlers approach the Ridgeway Avenue Bridge along with powerlines that cross over the Creek in one location.  Many gravel bars and sandbars can be seen throughout the stretch of Black Hawk Creek from Franck Park to Hope Martin Park.  Lastly, while not along Black Hawk Creek, the bladder dam downstream along the Cedar River is notable for its impact on the water level, navigation, and habitat of the creek.