Hoosier Creek Watershed All of Ely drains into Hoosier Creek, which runs north to south along the west side of Ely. Hoosier Creek, Hydrologic Unit Cod

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7 Hoosier Creek Watershed All of Ely drains into Hoosier Creek, which runs north to south along the west side of Ely. Hoosier Creek, Hydrologic Unit Code (HUC) , drains into the Coralville Reservoir, which makes Hoosier Creek a Class A-1 water body (Recreational Primary Contact). In addition, it is a Class B (WW-2) (Aquatic Life Warm Water Type 2). Hoosier Creek has a drainage area of approximately 17 square miles upstream of the Vista Road bridge. Exhibit 1: Hoosier Creek Drainage Area (Source: Iowa Flood Information System- Iowa Flood Center) In 2002, the Linn County Soil and Water Conservation District (LCSWCD) initiated the Hoosier Creek Watershed Protection Project. The project was intended to analyze the quality and availability of water, and a lack of public education on water quality issues in a rapidly urbanizing area which were problems in Hoosier Creek in southern Linn County and northern Johnson County. In 2002, nearly 15 percent of the land in the 14,891-acre watershed is urbanizing land. Practices installed on cropland and in urban areas include streambank protection, critical area seedings, grassed waterways, grade stabilization structures, newly created wetlands, and native landscape plantings. Today, the watershed has become even more urbanized, making water quality improvement projects in urban areas of the watershed even more important. In spring of 2009, information from IDNR Field Office 1 at Manchester, the IDNR stormwater coordinator, and from local news media demonstrated severe water quality degradation in the upper

8 portion of this segment of Hoosier Creek. These conditions were attributed to runoff of de-icing agents (propylene glycol and ethylene glycol) from the Eastern Iowa Airport at Cedar Rapids. The presence of high concentrations of glycols in surface waters can create high levels of oxygen demand such that levels of dissolved oxygen are too low to support the expected types of aquatic life (fish; aquatic macroinvertebrates). In addition, the hypoxic and anoxic conditions can result in aesthetically objectionable conditions such as unpleasant odors. In addition to impairment of general uses, these conditions also suggest impairment of the presumptive Class A (primary contact recreation) uses and Class B (WW1) aquatic life uses for this stream segment. Results of rapid biological sampling in May 2010 also suggested the aquatic life uses were impaired based on an evaluated assessment. Staff was only able to collect one species of fish (Creek Chub) in the segment. In addition, most of the abundant benthic macroinvertebrate taxa collected were tolerant of degraded water quality conditions and very few benthic macroinvertebrate taxa sensitive to poor water conditions were collected. Fall 2010 information, however, suggests significant improvement in the water quality conditions in this segment of Hoosier Creek. According to IDNR field staff, a collection system for de-icers was installed at the Eastern Iowa Airport in summer 2009 and the resultant reduction in the amount of de-icers moving to the stream has improved water quality. Due to the potential for ongoing water quality impacts, and due to the lack in in-stream monitoring data for either chemical/physical or biological parameters, this assessment segment will be added to Iowa s list of waters in need of further investigation. No ongoing water quality testing or monitoring has been completed since the completion of practices related to the Hoosier Creek Watershed Protection Project or since the sampling related to the airport de-icing issues. Rogers Creek Watershed Rogers Creek runs through Ely and discharges into Hoosier Creek within the Ely city limits. A significant portion of Ely drains to Rogers Creek. Rogers Creek has a drainage area of approximately 3.2 square miles. Rogers Creek has experienced significant sediment in the runoff in the creek. This is evidenced by the large amount of sediment which has been deposited in, and upstream of, the culvert under State Street. Sediment build up is obstructing approximately 25% of the culvert opening. The culvert was constructed in 2007 and over just 10 years has experienced this sediment build up. The culvert has an increased capacity from the previous bridge. This increased capacity of the new culvert allows the flows in the creek to spread out and slow down as they approach the culvert, resulting in the sediment dropping out of the runoff at the culvert. There are several potential reasons for the significant sediment build up. Ely has experienced significant growth in the past 10 years, including several developments which drain to Rogers Creek. This development activity involved significant soil disturbance which likely contributes to the sediment in the runoff toward Rogers Creek during rain events.

9 Exhibit 2: Rogers Creek Drainage Area (Source: Iowa Flood Information System- Iowa Flood Center) There is a pond that was constructed in the late 1990s on Rogers Creek within Ely. This pond provided improvements to the water quality on Rogers Creek as well as providing some flood reduction in areas downstream along Rogers Creek. In 2008, the dam for this pond failed, washing out the dam and depositing sediment from the dam as well as from the pond into areas downstream. The failure of this dam has contributed to water quality issues in Rogers Creek, specifically with regard to sediment. A repair of the dam was completed in 2011 which restored the pond and started providing the watershed quality improvements. Unfortunately this repaired dam also failed a few years later, washing significant sediment downstream again. No water quality monitoring has been completed for Rogers Creek. Pollutants of Concern Sediment Sedimentation within streams and rivers can have several detrimental impacts. The deposition of sediment often includes increased phosphorus levels in the streams. The phosphorus attaches to the

10 soil particles. Phosphorus primarily comes from fertilizer applications applied to urban lawns and agricultural fields. Too much phosphorus in the water can cause algae to grow faster than ecosystems can handle. Significant increases in algae harm water quality, food resources and habitats, and decrease the oxygen that fish and other aquatic life need to survive. Some algal blooms are harmful to humans because they produce elevated toxins and bacterial growth that can make people sick if they come into contact with polluted water, consume tainted fish or shellfish, or drink contaminated water. Another impact of sedimentation in streams is the reduction in the conveyance capacity of the stream. As the conveyance capacity of the stream is reduced, the runoff in the stream increases in velocity, which increases the amount of streambank erosion in the stream and cause additional flash flooding concerns. Many urban streams, Like Hoosier Creek and Rogers Creek, have very high velocities which cause flash flooding and significant streambank erosion. Urban Runoff Most of the runoff from Ely to Rogers Creek and Hoosier Creek is from urban developed areas with significant impervious area, including roofs, streets and parking lots. Runoff from these types of areas often has oils and greases from vehicles (hydrocarbons) in addition to significant sediment from snow removal operations. Urban runoff is often warmer water from pavements which drains directly to the creeks, adversely affecting aquatic life. Bacteria Bacteria in surface water is typically attributed to animal and human waste from feedlots, concentrated animal feeding operations, manure applied to fields, septic systems and improperly maintained municipal and community wastewater treatment facilities. Bacteria is typically measured by the number of colonies of E. coli bacteria present in a collected sample. High levels of bacteria pose a health risk to recreational users of the streams in the watershed. Since Hoosier Creek drains directly to the Coralville Reservoir, this is a significant concern. Nitrogen and Nitrates Surface waters in Iowa tend to have elevated levels of nitrogen and nitrates due to fertilizer application for urban lawns and agricultural fields. Excess nitrogen and nitrates in streams can cause increased algae growth, which has harmful effects on aquatic life and also can be harmful for humans. Nitrates are highly soluble in water can be easily transported in runoff to streams and rivers. Increased nitrate levels are a concern for drinking water sources for communities downstream. Watersheds Within Ely As previously discussed, all of Ely drains toward Hoosier Creek, either directly or via one of two minor creeks. The northwest part of Ely, including property along State Street and a portion of the older part of Ely, drains directly to Hoosier Creek. The majority of Ely, areas to the north of Main Street and east of Dows Street, drains to Rogers Creek while the newer Southbrook area, generally east of Rock Island Drive, drains primarily to Banner Valley Creek, which also drains to Hoosier Creek.

11 Exhibit 3: Ely Drainage Areas and Waterways Exhibit 3 shows the areas of Ely which drain to both Hoosier Creek and Rogers Creek. The area of downtown Ely has been further broken down into three additional drainage areas. These drainage areas provide the most densely developed areas of Ely and provide the best opportunities for implementation of water quality practices. Drainage Area A includes an area of apartment buildings and other multi-family residential development. This is the only area of Ely which has this type of development. There is significant runoff from this area due to a high percentage of impervious areas. The runoff in this area is high in sediment

12 from snow removal activities and also contains hydrocarbons from vehicles in streets and parking areas. The runoff from this area drains into Drainage Area B and then to Hoosier Creek. Drainage Area B is the oldest residential area of Ely. This area has rural section seal coat streets with ditches for conveyance of storm water runoff. The areas along Main and Dows Streets also include commercial buildings. The grain elevator in town is located within this drainage area and includes significant gravel surfaces which contribute to sediment in storm water runoff. The residential areas contribute nitrogen and phosphorus from lawn fertilizers and other chemicals. This area drains directly to Hoosier Creek. Drainage Area C is mostly commercial with some single family residences. Drainage along Rowley Street has been in issue with ponding water and erosion problems in large storm events. The gravel parking area near City Hall experiences erosion and requires repair after major rain events. This erosion is being deposited directly into Rogers Creek. This area also contains a high percentage of impervious surfaces. Runoff from this area drains directly to Rogers Creek. There are few water quality practices already installed in Ely and the City has been eager to incorporate some of these practices throughout the City. New developments have been providing storm water management designs which include water quality features and the City is considering requiring infiltration based practices for new developments. The downtown area is already fully developed so this is the area where it makes the most sense to implement water quality practices to provide the greatest impact. Its location close to Hoosier and Rogers Creeks also provides for maximum runoff capture and treatment of runoff for discharge to the creeks. Water Quality Improvements Projects Goals and Objectives Primary Goals - Improve water quality by protecting and improving the biological, chemical, and physical integrity of Rogers Creek and Hoosier Creek. - Reduce sediment loads from in and around the urban area of Ely. - Reduce the sources of hydrocarbons and other urban pollutants from the urban areas of Ely. - Reduce nutrient loads from Ely and surrounding agricultural areas. Secondary Goals - Implement urban storm water management practices that are consistent with the Iowa Storm Water Management Manual as an example to other communities in the Hoosier Creek Watershed. - Reduce runoff volume from in and around the urban area of Ely. Objectives - Implement storm water practices that provide infiltration and storage of runoff in the upper areas of drainages in Ely that will reduce sediment transport into nearby surface waters.

13 - Implement storm water practices that will reduce nutrients and other pollutants from entering nearby surface waters. - Implement storm water practices that reduce runoff volume through improved infiltration and storage at project sites. Outside Organizations The City of Ely has been working with two outside organizations on the identification of potential projects. The Linn County Soil and Water Conservation District (LCSWCD) and the Iowa Department of Agriculture and Land Stewardship (IDALS) have consulted with the City regarding the proposed projects. These organizations will continue to provide support during design and implementation of these projects. They will be consulted during the design of the water quality practices. The City of Ely also is considering applying for additional funding through the Water Quality Initiative (WQI) and these agencies will assist with the applications to that program for additional funding for water quality projects in Ely. A letter of support from the Linn County Soil and Water Conservation District is attached at the end of this report. Potential Water Quality Improvements Projects The intent of these projects would be to design them to treat the water quality volume (WQV) of 1.25 inches of rainfall in a 24 hour period. Some practices may also include provisions for storing and treating up to the channel protection volume (CPV), which is 2.4 inches of rainfall in a 24 hour period. The practices will include overflow or bypass features for storms larger than the above events. A - Permeable Pavers on Main Street between Dows Street and Traer Street This project would replace the existing seal coat paving on Main Street between Dows Street and Traer Street with permeable pavers. The permeable pavers will provide a reduction in the sediment and nutrient load from the runoff from this street. This project would provide water quality improvements in Drainage Area B. B - Permeable Pavers on City Hall Parking Lot The City of Ely is in need of additional parking near City Hall. St. John s Methodist Church is near City Hall and owns property adjacent to City Hall. The church and the City reached an agreement to construct a parking lot on property currently owned by the church. This area of Ely experiences drainage problems and runoff from Rowley Street drains through gravel parking area to Rogers Creek. Adding permeable pavers to the design of this parking lot will replace the gravel parking and capture and treat that runoff before discharge to Rogers Creek. This project would provide water quality improvements in Drainage Area C.

14 C - Bio-Retention Cells Along Downtown Streets The streets in the older downtown part of Ely (State, Main, Traer and Walker Streets) are rural section roadways with ditches. The installation of bio-retention cells in the ditches in these areas will provide treatment of the runoff from these streets and adjacent impervious areas. Bio-retention cells provide excellent removal of nutrients and sediment from storm water runoff. This project would provide water quality improvements in Drainage Area B. D - Bio-retention Cell Behind Fire Station There is an existing ditch which carries runoff to Rogers Creek from Dows Street. Installation of a bioretention cell along a portion of this ditch will provide treatment of the runoff prior to draining to Rogers Creek. Re-grading of the ditch in this area to slow down runoff and provide a vegetated swale or filter strip is another option to treat the runoff at this location. A bio-retention cell which provides treatment of the fire station building and parking only is also considered as a part of this project. This project would provide water quality improvements to Rogers Creek. E - Bio-retention Cell or Bioswale Behind Northgate Apartments There is an existing small detention basin located behind the apartments on Northgate Avenue, between the apartments and the homes on Fuhrmeister Street. This basin has experienced a buildup of sediment from streets and parking lots which has reduced the storage capacity of the basin. This project would convert the detention basin to a bio-retention cell or bioswale which would provide better removal of sediment and nutrients from the runoff which drains to this basin. This project would provide water quality improvements in Drainage Area A. F - Reconstruct Dam for Pond on Rogers Creek This project would reconstruct the dam for the existing pond on Rogers Creek. The dam has washed out twice, most recently since it was last reconstructed in This pond provides significant reduction in the sediment and nutrients in Rogers Creek by providing a wet detention basin. This project would provide water quality improvements in Rogers Creek for the area downstream of the dam. Sediment Forebays at Storm Sewer Outlets Although there is no practice like this outlined in the Iowa Storm Water Management Manual (ISWMM), one idea considered by the City is to provide small forebays at existing storm sewer outlets which would capture sediment prior to deposition into creeks. There are around a dozen storm sewer outlets which outlet to Hoosier and Rogers Creek but they are mostly located on private property. Although this practice would provide good reduction in sediment load to the creeks, it is not given a high priority due to their locations and the limited information in the ISWMM regarding their design and implementation.

15 Preferred Projects The following projects are preferred by the City of Ely as they have the most impact on water quality improvement in Ely. Permeable Pavers in City Hall Parking Lot this project is located close to Rogers Creek and presents a favorable location to capture and treat runoff from Rowley Street and other upstream impervious areas Bio-Retention Cell Behind Northgate Apartments there is a large impervious area upstream of this area and this project would provide treatment of this runoff. This area of town has experienced drainage issues in the past so this project will improve the drainage while promoting infiltration and improved water quality. Bio-Retention Cells along Downtown Streets the downtown streets have rural street sections with ditches which collect and convey runoff from the streets and other impervious areas. The City is planning a project for improvements to State Street which will likely make State Street the favorable location for installation of these practices. This entire downtown area drains directly to Hoosier Creek which makes this area a preferred location for water quality improvements. Project Locations and Land Ownership Exhibit 4 shows the locations of the projects outlined above. The preferred projects are shown in red while the other projects are shown in blue. The preferred projects were selected in part because the City either owns the property or has an easement over the property on which they would be constructed. The City also owns the fire station property. The property on which the Rogers Creek pond and dam is located is privately owned. It is the City s preference to work on projects within existing rights-of-way or easements. Expected Water Quality Improvements by Project Type The Iowa Storm Water Management Manual (ISWMM) outlines the expected water quality improvements by type of project. Bio-retention Cells Bio-retention cells typically provide reduction in total suspended solids (TSS) and hydrocarbons and provide some removal of nutrients. Reductions in TSS (sediment) are typically 50% or more with reduction in Nitrogen and Nitrates typically around 40%. Removal of phosphorus is not as good, typically around 5-10% depending on the depth of the ponding in the cell. Removal of heavy metals such and zinc, copper and lead are very good with bio-retention cells, with typically 90% or more removal.

16 Exhibit 4: Project Locations Permeable Pavers Permeable paver systems are typically efficient at removal of nutrients with 80% removal of nitrogen and phosphorus in average systems. These systems are also efficient at removing heavy metals, with typical removal rates of 90% for zinc, copper and lead through these systems. Although permeable pavers also remove total suspended solids, this often results in these sediments clogging up the system and reducing the capacity and effectiveness of the system. The pavers will require more frequent maintenance if sediment removal is desired through these types of systems.

17 Bioswale Bioswales are similar to bio-retention cells but are constructed on a slope with check dams which provide detention and slow down runoff and promote infiltration. The bioswales provide better removal of total suspended solids, upward of 90% removal, while also providing similar removal rates of other pollutants as bio-retention cells. Removal of heavy metals and hydrocarbons are typically near 90% removal with bioswales. Wet Detention Construction of wet detention basins provides very good treatment of all types of pollutants. Settlement within the pond is the primary method of pollutant removal, especially for total suspended solids. Algae and other vegetation within wet ponds also provide removal of nutrients. Other biological processes help with pollutants removal. Typical removal rates are near 85% for total suspended solids and around 30-50% for nitrogen, phosphorus and heavy metals. Evaluation Procedures and Measures The City intends to work closely with project partners during design and implementation of the projects to ensure that project goals are being met with the projects selected. Long term maintenance of the projects that are implemented will be the responsibility of the City of Ely with support from project partners. The knowledge and experience of LCSWCD and IDALS staff will be utilized along the entire project process, including recommendations regarding maintenance of practices. The following measures will be used to evaluate whether the project has met the intended goals: - Is the storm water runoff captured and treated as designed? Do they provide the greatest water quality benefit to the area treated? - Are the practices effective in reducing runoff in the project areas? - Are practices being maintained as recommended by partner agencies? - Is the public aware of the project and the intended outcomes from the project? Anticipated Project Schedule The water quality projects would coincide pretty closely with the wastewater project with both projects being designed over the winter of 2018 and construction to be completed in The anticipated project schedule is as follows: Receive Notice of Project Acceptance December 2018 Meet with Project Partners to Determine Project Location(s) January 2019 Project Design Spring 2019 Estimated Letting Date May/June 2019 Construction Summer 2019 Final Acceptance and Closeout Fall 2019

18 Proposed Budget and Funding Sources The City of Ely s SRF request amount is $1,779,000 for the trunk sewer project. Based on that, it is estimated that approximately $175,000 in funding will be available through the Sponsored Project program. The City also is intending to pursue additional funding through the Water Quality Initiative (WQI) program later in the fall of The intention is provide funding for design work and construction of the project. The City intends to work with project partners if the funding is awarded to determine which projects will provide the most water quality benefits. The City has listed preferred projects above which will be the initial intended projects but if other similar projects provide more benefit to the water quality of Rogers Creek and Hoosier Creek, they will be scored higher and implemented first as budget allows. The City has planned for 10% contingency and may also be willing to include additional local funding in order to complete the preferred projects. Preliminary Communication Plan The City of Ely intends to provide communication in several different ways, including project open houses or workshops, social media posts and direct communication with affected stakeholders. The City also sends out a newsletter with City utility bills that will inform and educate the public regarding the projects. One on one meetings with affected property owners will be critical to project success. The City Council and Mayor will be actively involved in the project and Council meetings and community events provide another opportunity to discuss the project with the public. Communication with project partners during the design and implementation of the project will be important. The more involved and interested that all project partners remain during the project, the more likely the project will be successful.

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