lower brookside drainage study - independence, ohio

22999 Forbes Road, Suite B • Cleveland, Ohio 44146-5667

Phone: 440.439.1999 • Fax: 440.439.1969 • www.cvelimited.com

LOWER BROOKS IDE DRAINAGE STUDY P r e p a r e d f o r :

C i t y o f I n d e p en d e nc e 6 8 0 0 B r e c k s v i l l e R o a d I n d e p e n d e n c e , O h i o 4 4 1 3 1

M a r c h 1 4 , 2 0 1 2

CITY OF INDEPENDENCE, OHIO LOWER BROOKSIDE DRAINAGE STUDY MARCH 14, 2012

CONTENTS Executive summary ............................................................................................... [i] Introduction ............................................................................................................ 1 Acknowledgements ................................................................................................. 1 Authorization .......................................................................................................... 1 Recommendations ................................................................................................... 1 Background Information ......................................................................................... 2

Lower Brookside Drainage Area ......................................................................... 6 Floodplains ......................................................................................................... 8 Lower Brookside Soils ....................................................................................... 9 June 22, 2006 & August 15, 2011 Storm Events ............................................... 10

Public Input & Information Gathering ................................................................... 11

Analysis of Resident Surveys............................................................................ 11 Site Visits ......................................................................................................... 13 Public Meeting ................................................................................................. 13 Stakeholder Meetings ....................................................................................... 13 Phone Interviews .............................................................................................. 14 Database Creation ............................................................................................. 15

Lower Brookside Watershed ................................................................................. 15

Watershed & Stream Characteristics ................................................................. 15 Noted Watershed Drainage Issues ..................................................................... 20 Past Studies of Drainage Issues with the Watershed .......................................... 22 Conclusions and Recommendations .................................................................. 23

Other Recommendations ....................................................................................... 33


[i]

EXECUTIVE SUMMARY The City of Independence was incorporated as a village in 1914, approved a municipal charter in November 1958 and finally became a city in November of 1960. A large portion of the local heritage stems from the city’s commercial quarry of sandstone and shale. By 1850 with a total of 1,485 residents, independence was one of the nation’s foremost suppliers of building stone. And in 1940 the completion of the Willow Cloverleaf at Brecksville and Granger roads that was one of the first highway interchanges in the county, many new businesses located to Independence and the city became industrialized. The development of Independence appears to have been consistent with the common building practices at that time which employed extensive manipulations of the natural environment in order to maximize the use of land resources. The result was streams replaced by culverts, loss of flow capacity within remaining stream corridors, extensive areas of impervious surfaces, few stormwater flow controls and homes built much too close to consistent flood hazards. As awareness to the impacts of development grew in the last quarter of the twentieth century, Independence did, by and large, keep pace with the times and consistently adopted measures to control development and prevent further impacts from development. However, areas with significant flooding problems stemming from the past practices presented difficult community choices. The City of Independence received a loan from Water Pollution Control Loan Fund (WPCLF) to perform a drainage study for the Lower Brookside Area. The City of Independence advertised request for proposals for the Lower Brookside Watershed Study to perform a watershed analysis and give feasible options to improve water quality and flooding within the watershed. Chagrin Valley Engineering, Ltd. (CVE) was determined to be most qualified to perform the study and was engaged by the City of Independence to undertake this study. The purpose of this study is to document public input concerning flooding issues, review past studies and provide recommendations to improve conditions throughout the community. As part of its work, CVE reviewed flooding questionnaires solicited from residents that live in the Lower Brookside Watershed, created a Geographic Information System (GIS) to map properties impacted by flooding, performed phone interviews with residents, made site visits and held public meetings. The result of these efforts is a concise documentation of problem areas and circumstances that will serve as a resource when future infrastructure projects are considered. The recommendations provided herein generally fall within the following categories: • City of Independence should work cooperatively with adjacent communities

(Brecksville and Broadview Heights) to implement better stormwater management controls for the watershed.


[ii]

• The City of Independence take immediate steps to remove debris and obstructions along the drainage corridor and establish and on-going maintenance plan for all existing creeks, streams and culverts along the Lower Brookside area and its tributaries.

• The City should continue to notify and educate residents in the Lower Brookside Area of the well known and long standing flooding issues in that area of the community.

• The City should consider a program to purchase properties, such as the program via

FEMA, within the watershed that have a documented history of consistent re-occurring structural flooding.

• The City should work cooperatively with the property owners on Sprague Road, Brettin

Court and Kingscote Park to create a more uniform stream channel as well as reestablishing a floodplain from Sprague Road to Brecksville Road.

• The City of Independence should work cooperatively with the City of Broadview

Heights and its residents to install a regional detention basin located in Broadview Heights on the west side of I-77.

• The City should install a detention basin at St. Maron on Brookside Road.

• The existing bridge located at St. Maron be removed. The City would need to secure

an easement for access to the structure for demolition.

• The City of Independence should work cooperatively with the City of Broadview Heights and Brecksville to improve the drainage of Sprague Road including the addition of curb and storm sewer along the corridor.

• The City of Independence should work with the homeowners along the north side of

Brookside Road to help alleviate the chronic rear yard flooding. It is not recommended the city take ownership of additional easements, but provide technical assistance to improve the cooperation between neighbors.

• CVE recommends that the City look into areas to put into practice best management practices (BMPs) that will infiltrate flow generated by existing impervious surfaces like bio-retention swales and porous pavement.


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INTRODUCTION In 2011 Northeast Ohio had seen a record setting amount of rainfall and on August 15, 2011 a storm event resulted in significant flooding in the Lower Brookside Watershed. The storm event of 2011 is the latest in a pattern of community wide flooding events that are seemingly occurring with greater and greater frequency. In September of 2011 the City of Independence Council Members authorized the Administration to contract with Chagrin Valley Engineering, Ltd. (CVE) to perform a study of stormwater related issues that affect the Lower Brookside Drainage Area. The purpose of CVE’s study was broken into five tasks. The first task was to identify and engage the watersheds stakeholders, set up public meetings and meet with stakeholders. The second task was to evaluate the existing conditions of the drainage area and review the available city information on flooding/drainage complaints. The third task was to identify the problem areas in the watershed through public participation, including public meetings and resident input. The fourth task of the study was to give the City feasible solutions including structural and non-structural measures to mitigate each of the potential adverse impacts so that the City can establish performance goals for their stormwater management systems. The final task was to provide a breakdown of project cost for the feasible solutions given including potential project funding.

ACKNOWLEDGEMENTS Chagrin Valley Engineering, Ltd. wishes to thank the City of Independence Council Members and the following individuals: Gregory P. Kurtz, Mayor and Donald J. Ramm, P.E., City Engineer. CVE would like to especially thank the numerous residents and concerned citizens that took the time out of their busy schedules to speak with CVE representatives, fill out questionnaires, provide background documentation and attend public meetings. The courtesy, cooperation and insights extended to Chagrin Valley Engineering, Ltd. by these individuals and/or members of their staff is immensely appreciated and was invaluable in the preparation of this study and report.

AUTHORIZATION Chagrin Valley Engineering submitted a cost proposal and scope of services to City of Independence Officials on September 6, 2011. City of Independence Council Members considered the cost proposal and scope of services at their September 13, 2011 meeting and granted approval with minor modifications.

RECOMMENDATIONS The recommendations presented within this report were formulated by CVE staff based on general engineering judgment and municipal government experience. These recommendations will have the potential to improve stormwater management conditions in the Lower Brookside Drainage Area in the City of Independence with regard to one or more of the following conditions; flood intensity, flood recurrence intervals, public health, public safety or public welfare. All of these recommendations require additional


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technical, legal, political and/or financial evaluations prior to implementation to insure feasibility, cost effectiveness and alignment with community priorities.

BACKGROUND INFORMATION The City of Independence is located in Cuyahoga County, Ohio approximately 12 minutes south of downtown Cleveland. Independence is approximately 9.6 square miles in size. The 2010 census recorded a city population of 7,133 residents with the total housing units for the city being 2,770. Independence is home to the convergence of I-480 and I-77 and is home to over 1,300 businesses with an estimated 25,000 employees. As a result of its suburban location and freeway access, the City of Independence contains very diverse land uses including urban commercial, office complexes, single family housing and mixed forest land. Likewise the housing stock within the City is a mix of single family homes on small lots (three fourths of an acre or less) and single family homes on large lots. The City’s Street Map is depicted in Figure 1, and the Land Use Plan is shown in Figure 2 while the Zoning Map is shown in Figure 3. Since the early portion of the twentieth century residents have been drawn to the City of Independence by its suburban / rural atmosphere and its proximity to the nation’s first interchange. Over the years momentum built and Independence saw significant development in the 1970’s. These developments also exhibit consistent manipulations of natural drainage systems in order to accommodate the higher housing densities. Throughout the more urban portions of the city, stream channels were likely relocated, straightened, narrowed and/or impeded in order to facilitate the construction of roadways, housing lots, utilities and appurtenances.


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City of Independence Street Map – Figure 1


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City of Independence Land Use Map – Figure 2


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City of Independence Zoning Map – Figure 3


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Lower Brookside Drainage Area The Lower Brookside Drainage Area is located in the southwestern most portion of the City limits. Along with the City of Independence, the cities of Broadview Heights and Brecksville are also included in the Lower Brookside Watershed. The Lower Brookside Drainage area flows from west to east as shown in Figure 4. The grade change across the area starting on the west side of I-77 to State Route 21 is approximately 160 feet and drops from State Route 21 to the Cuyahoga Valley National Park almost 250 feet. There are a total of 382 residents from the City of Independence that live in the watershed, as well as 116 residents from Broadview Heights and 9 residents from Brecksville. The total drainage area (including all three of the municipalities) is approximately 596 acres. The heart of the drainage area consists of a channel flowing in a northeast direction that begins in Broadview Heights then is conveyed by culverts under I-77 through the Cuyahoga Valley Community Church and into the City of Independence. The stream then crosses Sprague Road through a 4’x3’ concrete box culvert and then flows in an open channel that is located between the rear yards of the residents on Sprague Road and Kingscote Park. The open channel continues to flow in the rear yards until it crosses under Brecksville Road in a 5’x8’ concrete box culvert. The stream then flows in an open channel that is located in the rear lots of Montello and Brookside Roads here the existing stream picks up creeks from the rear yards of Montello and Dalebrook Roads as well as a drainage ditch that drains the rear yards of Dalebrook and Dalepoint Roads. There the channel crosses under Brookside Road through an existing concrete culvert, outlets to an existing channel that runs along Brookside Road and flows north eventually terminated into the Cuyahoga River and finally into Lake Erie. The Cuyahoga River and its tributaries drain 813 square miles or 520,320 acres and the Lower Brookside Drainage Area makes up 596 acres of that total area. The Lower Brookside Drainage Area mainly consists of ½ to 1 acre residential lots but also includes two non-residential properties. This includes a portion of the 22.3 acre parcel located between Sprague Road and Wallings Road owned by Cuyahoga Valley Community Church, 9.8 acres are actually included in the Lower Brookside Drainage area. The other site is the 22 acre St. Maron’s site located off of Brookside Road, plus a portion of I-77 that runs through the City of Independence and the City of Broadview Heights, the total contributing area from Ohio Department of Transportation’s (ODOT) property is approximately 51 acres (38 acres of pervious/grass and 13 acres of impervious/pavement) primarily made up of grassy area. The total impervious area in the 596 acre watershed including ODOT’s property is approximately 81 acres about 13.6%. The only zoning classification in the Lower Brookside Drainage Area in Independence is U-1 - single family zoning. In the drainage area there are not many opportunities for future development within the City limits. The only portion of undeveloped land in the watershed is located outside the city limits in Broadview Heights, west side of I-77.


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Lower Brookside Drainage Area – Figure 4


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Floodplains The current Federal Emergency Management Agency (FEMA) Flood Insurance Rate Maps (FIRMs) for the City of Independence were revised December 3, 2010. FIRMs delineate the special flood hazard areas, commonly known as floodplain areas, which have been developed and /or accepted by FEMA based on historic records, meteorological data, engineering studies, stream properties, open-space conditions and flood control work infrastructure. The maps show areas subject to inundation during various storm recurrence intervals so that local municipalities can promulgate regulations to promote public safety and protect private property. To achieve these goals FEMA requires local governments to pass flood damage prevention ordinances to regulate the placement of fill and structures in floodplain areas. The City of Independence adopted a Flood Damage Reduction ordinance December 11, 2007. This ordinance defines the areas of special flood hazard within the City as identified on the Flood Insurance Study and shown on FEMA maps or based on other studies and /or maps which may establish a flood protection elevations, delineation of the 100-year floodplain, floodways or delineation of other areas of special flood hazard approved by the City. The basis of the ordinance is to regulate the areas that experience periodic flooding by requiring a Floodplain Development Permit for any development activity including filling, grading, construction, alteration, remodeling, and alteration of any watercourse that is within or in contact with any identified special flood hazard. The ordinance also dictates what development is allowed in the flood hazard and what steps need to be taken to receive a Floodplain Development Permit. The FEMA FIRMs are updated from time to time due to the natural tendency of streams to change, the occurrence of new development and advancements in the accuracy of various mapping tools. As these maps are updated parcels of land and structures that once were not in the floodplain may now be located within the district or vice-versa. The latest FEMA maps are available to the public via the City and FEMA. The latest FEMA map for the City of Independence is depicted in Figure 5. The Flood Insurance Rate Map for the City of Independence does not cover any portion of the Lower Brookside Watershed. Even though many residents in the watershed have experienced structural flooding in the past, the latest updated FEMA maps do not call out any part of the Lower Brookside Area as a special flood hazard area.


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City of Independence FEMA Map – Figure 5

Lower Brookside Soils The soils in the Lower Brookside Drainage Area mainly consist of poorly-drained clay loam soils. Most of the drainage area is located around floodplains and headwaters of streams and consist of “wet” soils that are moderately to poorly drained. There is also a considerable amount of “Made Land” in the area brought on by the significant development along the Interstate 77 corridor. The United States Department of Agriculture (USDA) publishes a soil survey for each county in each state. The survey


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describes the types of soils present in each county, provides engineering and agricultural characteristics of each soil type and includes a map that depicts the soils found throughout the county. The Cuyahoga County, Ohio Soil Survey noted as being “Current” and is available for review on the USDA website, www.usda.gov. To classify the hydrology of various soil types the USDA developed the Hydrologic Soil Group classification system. The ratings described the physical drainage properties of each soil. An “A” rating correlates to a well drained and highly permeable soil while a soil type with a rating of “D” is poorly drained which produces greater runoff. The Lower Brookside Drainage area consists of mostly “C” and “D” type soils that can be classified as poorly drained, due to most of the area being in lowland areas along the stream banks. It is also important to note that the “Made Land” in developed areas is noted to have poor permeability. In general the characteristics of the existing soil types found in the Lower Brookside Drainage Area have a high runoff potential with low infiltration rates decreasing the time of concentrations in the watershed which in turn will increase the flow of stormwater throughout the watershed. June 22, 2006 and August 15, 2011 Storm Events On August 14, 2011, around 12:30 in the afternoon, precipitation began in the Independence area. According to the weather station located in Parma, Ohio on August 14, 2011 the area received 1.84 inches of rainfall and on August 15, 2011 the area received an additional 1.90 inches of rainfall. The weather station in Parma records rain intensities every fifteen minutes with the highest intensity of the August storm event being 0.94 inches per hour. The peak 24-hour rainfall for the August 14th and 15th storm was a total of 3.55 inches. In regards to the Storm Event on June 22, 2006 precipitation began to fall around 9:30 in the evening on June 21, 2006. The storm continued throughout the day of June 22, 2006 and according to the weather station in North Royalton there was approximately 1.10 inches of rainfall on June 21, 2006 and 2.7 inches of rainfall on June 22, 2006. The peak 24-hour rainfall for the June 21st and 22nd storm was a total of 3.80 inches. In order to quantify all storm events, the Ohio Department of Transportation has developed storm rainfall frequency relationships and a corresponding table to compare rainfall amounts to storm durations. This table compares the amount of rainfall over a certain period of time which in turn corresponds to a certain recurrence interval of the storm event. These recurrence intervals include the 1-yr, 2-yr, 5-yr, 10-yr, 25-yr, 50-yr and 100-yr storms. The definition of a 10-yr storm for example is that there is a 10% or 1 in 10 chance every year that a storm event that records from 3.4 to 3.9 inches of rain over a twenty four hour period will occur. As stated above the storm event on June 22, 2006 and August 15, 2011 produced 3.55 and 3.80 inches respectively of rainfall and as such classifies each event as a 10-year storm.


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PUBLIC INPUT & INFORMATION GATHERING Upon receiving authorization to proceed with this study, CVE began a multi-dimensional process to collect public input and gather information related to the public system of drainage within the Lower Brookside Drainage Area. The initiatives undertaken by CVE include analysis of resident surveys, site visits, phone interviews, public meetings, stakeholder meetings and database creation. Each of these initiatives is described in the following pages. The results of these various efforts directed the course of this study and thereby led to the formulation of the recommendations presented herein. Analysis of Resident Surveys The number one priority after CVE receiving approval for the Lower Brookside Drainage Study was to put together a resident questionnaire for the residents in the watershed. With the help of City officials, a resident survey was prepared and distributed to the Lower Brookside residents concerning flooding issues. The purpose of the questionnaire was to document the location, extent and type of drainage issues that the residents have experienced. The City distributed questionnaires to residents as well as had surveys available for residents to pick up at the public meeting and at the Independence Engineering Department. As of the publication of this report, fifty six (56) questionnaires have been filled out by residents and returned to the City. The completed questionnaires were in turn provided to CVE for logging, mapping and review. The completed questionnaires will serve as an important resource for the City going forward in its efforts to plan public drainage system improvements. Copies of the returned questionnaires are provided in Appendix “A”. Upon receipt of each completed questionnaire CVE performed a thorough review of the information provided. Each questionnaire was categorized by whether the issue was storm sewer or sanitary sewer related, the recurrence interval and the extent to which the flooding impacted a residential structure. Out of the fifty six (56) surveys provided to CVE, thirty three (33) surveys indicated flooding of structures. A majority of the 33 residents that experienced structural flooding noted stormwater flooding in the basement. The majority of the surveys that indicate structural flooding have experienced flooding of their basements prior to 2011. Most of the residents that experience structural flooding have experienced flooding multiple times in the past. These residents mainly live in the areas of Brookside Road, Dalepoint Road, East Sprague Road and Kingscote Park, a few of the residents in these areas experience flooding in their basements multiple times a year. Also important to note that three (3) surveys indicate that residents that experienced structural flooding indicated that it was due to a sanitary backup in their basements during heavy rainfall. Two of these residents are located on Brookside Road and the other lives on Dalebrook Road. Of the other twenty-three (23) questionnaires that indicated the residence did not experience any structure flooding, seventeen (17) of those surveys noted that overland flooding or flooding of the yards occurred. Overland flooding does present a safety


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concern for the public and as such was noted by some survey respondents who indicated massive amounts of rushing water in their streets and rear yards and noted concerns about injuries to small children and pets during these “flash floods”. All of the residents that completed surveys were able to provide significant historical perspective as well as photographs, videos and drawings which documented the circumstances encountered at their home during flood events. While it may not be feasible to address all of the concerns expressed by the residents, the information and data collected will serve as an important resource during future discussions over the type and extent of flood mitigation projects to be implemented. Electronic copies of all the documents and files provided to CVE by residents during the course of this study have been placed on a compact disk and included with this report. The map shown below, clearly depicts the correlation of survey respondents that have experienced flood events and the location of those parcels.


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Site Visits CVE staff performed site visits to the Lower Brookside Drainage Area on many different occasions. The first site visit was to take a tour of the areas prone to flood in the watershed and to collect background information on the study area. Other site visits included collecting photos of the watersheds characteristics and measuring the streams cross sections at various points along the watershed. Public Meeting The Lower Brookside Drainage Study Public Meeting was held October 25, 2011 at the City of Independence Civic Center. Notice for the event was given with the survey packet that was distributed to all of the watershed’s residents, was posted on the website and announced at other public meetings. The meeting introduced CVE to the residents of Independence and provided yet another venue to collect additional information from the public. The forum was attended by approximately 45 Independence residents. Topics of discussion at the meeting ranged from historic flooding conditions to green infrastructure to establishment of a stormwater utility. Residents were free to voice any concerns that they might have concerning the stormwater management issues and give additional information of their specific flooding problems as well as to complete and turn in a resident survey. Stakeholder Meetings The Lower Brookside Drainage Area is located not only in Independence but also in Broadview Heights and Brecksville. The headwaters of the watershed begin in Broadview Heights south of Sprague Road and west of I-77. CVE indentified the City of Broadview Heights has an important stakeholder due to the amount of undeveloped land in the watershed as well as the expansion of Cuyahoga Valley Community Church (CVC) that is also located in Broadview Heights. CVE along with Mr. Donald Ramm, the City Engineer for Independence, met with Broadview Heights’ officials to inform them of the drainage study, to get any feedback on any flooding in their city located in the watershed and the possibility of joint ventures to curb any structural flooding in the watershed. Broadview Heights informed CVE that there have been no flooding complaints from any Broadview Heights residents located in the watershed. Officials also stated that the CVC stormwater detention basins are functioning properly and are inspected by the city on a yearly basis. CVE also inquired about the undeveloped land on the west side of I-77 in Broadview Heights, officials did mention that a paper street runs through the area but no development is in the works. Broadview Heights’ officials also stated that it is the city’s intention to apply for grants to perform improvements along Sprague Road this may include storm improvements, improving the cross section of the roadway and pavement rehabilitation. On December 21, 2011 CVE and Mr. Ramm met with members of the staff from ODOT District 12 and ODOT Central Office. The meeting was set up to discuss the issues related to the Lower Brookside Drainage Area and how ODOT may help to elevate the flooding issues downstream of I-77. The other possible help might be their knowledge


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of available funding to aid the City in creating a solution. Over the last few years ODOT has completed the installation of an additional lane in the north and south bound direction on I-77 through the Independence corridor. The additional lane has made the City question the effect on the already stressed storm sewer system. ODOT continued to confirm the design was correct and that ODOT captured the more frequent storm events in exfiltration trenches or other water quality structures as required by the Ohio EPA. ODOT did mention, if the City found the roadway drainage for the new lane was re-routed or re-directed into an different drainage area that negatively impacted the downstream storm sewer they would evaluate assisting the City to elevate the problem. We discussed the possibility of utilizing State funds to create a detention basin. They told us there are no monies available to accommodate this request. We also discussed meeting on-site to evaluate the options available at the discharge of the thirty-three inch (33”) and fifteen inch (15”) culverts into the existing one foot (1’) by eighteen inch (18”) drainage structure with a twenty-four inch (24”) discharge pipe on the south side of Sprague Road in Broadview Heights just east of I-77. The meeting with ODOT has not yet occurred but a follow up memo will be attached to the final report to discuss the final conclusion. A few weeks after the meeting with ODOT, specifically January 10, 2012, CVE met with Derek Schafer from the West Creek Preservation Committee. During this meeting Derek expressed an interest in assisting the City to hold parcels that would be critical in re-establishing the watercourses needed flood plain area. He also mentioned the use of other BMPs within the area to assist the residents in reducing the amount of discharge from impervious surface – rain gardens, rain barrels, bioswales, pervious pavement within cul-de-sacs, etc. He realized the small impact on the large drainage shed but also realized the benefit of having multiple smaller BMPs throughout the Lower Brookside Area. Phone Interviews A sampling of residents who experienced flooding were contacted by phone and interviewed in order to collect more in depth information on the type of flooding and their particular experiences. Residents were selected for phone interviews based on the information they provided on the flooding questionnaire including location of the property, the type of flooding that occurred and the frequency of the flooding. In total, eleven (11) of the thirty-three (33) residential surveyed noting “…..flooding had occurred on their property….” were contacted for a follow up phone interview. Of the eleven that were called for a follow up interview, only four of them responded. The following table presents a quantitative summary of the survey responses and phone interviews conducted.

Watershed Name No. of Surveys

Collected

Basement Flooding Reported

No Basement Flooding Reported

Residents Called But No Answer & No Return Call

Residents Spoken

To

Lower Brookside 56 33 23 7 4


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Database Creation In order to document the survey responses and provide a useful analysis tool for future stormwater management initiatives within the watershed, a Geographic Information System (GIS) was created by CVE as part of this study. The utilization of GIS facilitates the accumulation of data from various sources, allows creation of interrelated databases, enables custom queries of the collected data and provides a mechanism to produce visualization aides such as maps and graphs. CVE utilized the ESRI ArcView software package to assemble sets of data provided by the Independence Engineering Department, resident flooding questionnaires and Cuyahoga County. The data in the GIS includes flooding questionnaire responses, property lines, elevation contour lines, aerial photography, streets, street names, watershed boundaries, streams, and FEMA floodplains. Each category of response in the resident flooding questionnaire was entered into the GIS. As such, searches of that data are easy to undertake and document visually. The GIS data collected will be transferred back to the City of Independence Engineering Department prior to the publication of this report. The assembled data can be viewed in custom ways by use of a free software package known as ArcReader, also produced by ESRI and available for download at www.esri.com. The utilization and expansion of the GIS system started under this study will provide a powerful decision making tool that serves to retain knowledge as staff members change over time.

LOWER BROOKSIDE DRAINAGE AREA

Watershed & Stream Characteristics

The Lower Brookside Watershed begins in Broadview Heights bordered by Sprague Road to the North, portions of Wright Road, Skyline Drive and Mill Road to the west and by Wallings Road to the South. The watershed drains one to two acre lots in Broadview Heights which also includes some undeveloped, wooded and land-locked parcels just west of I-77. Three separate channels form in this area that are conveyed under I-77 by concrete culverts sized 42”, 33” and 36” respectively. It is noted through residential interviews that runoff from Skyline Drive is like a river during large storm events and overwhelms the Sprague Road system adding to the problems downstream. In 2008 ODOT began an improvement project of the I-77 freeway which included work within the Lower Brookside Drainage Area. The project mainly consisted of pavement rehabilitation, lane widening with additional lanes, drainage improvements and construction of sound walls. Through these improvements ODOT added about 4.5 acres of impervious surface (pavement) within the Lower Brookside Watershed, which is a 53% increase of pavement area on ODOT’s property. The improvements did not significantly upsize any of the storm sewers and did not change the drainage patterns within the watershed. To better describe the impact on the watershed from the improvements by ODOT, CVE quantified the curve number for both the pre and post conditions of the I-77 improvements. The curve number is expressed as a number between 40 and 100, higher the number the greater the runoff and amount of stormwater to be discharged from a site. The curve number for the ODOT property


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prior to the improvements in 2008 was 83. After the construction of the additional lanes the curve number was increased to 85. The use of the curve numbers can then be correlated directly to the amount of run-off generated from the site. Based on the above referenced pavement additions, we evaluated the amount of change in volume created by the additional lanes. In this case when comparing the pre vs. post run-off volumes, the total run-off volume increase for the 1-year storm event between the pre and post would be 13% (pre volume - 131,189 cf and post volume – 148,166 cf). Although ODOT is exempt from local storm water management regulations, we wanted to provide an illustration of what restrictions would be imposed if this would be a typical development. Using the City’s stormwater management requirements for a developed area, the above referenced change in volume would require a typical development to reduce the flow for the 1-yr and 2-yr discharges to the 1-yr pre-existing rates and all other storm events would be required to not discharge more than the pre-developed rates. The storm sewer on I-77 was designed to handle the water quality as required by the Ohio EPA. The water quality is attained by installing exfiltration trenches/boxes. These exfiltration trenches/boxes adhere to the water quality standards required by the Ohio EPA but they do not address the water quantity issue. The pictures below were taken on the Cuyahoga Valley Church (CVC) property and depicts the characteristics of the streams as they outlet under I-77 and flow through Broadview Heights. The streams in Broadview Heights are primarily in undeveloped areas. This allows the streams to over top it’s the banks and meander across the property(s) as flows increase. The increased area of the stream allows the velocities of the streams to be slowed and thus creating more stable banks to be formed.

Photo looking nort h at CVC, drive culvert to the right and I-77 to the left

Photo of creek exiting CVC drive culvert looking east


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In 2005 the CVC that is located in Broadview Heights constructed an additional drive entrance and parking for the existing church. Thorson Baker and Associates prepared the improvement plans and drainage calculations for the proposed work which was approved by the City of Broadview Heights Engineering Department. The CVC area tributary to the Lower Brookside Watershed is 9.8 acres. The developed area was designed to meet the storm water management requirement of Broadview Heights. Based on the calculations, the area tributary to the Lower Brookside Drainage area will discharge less than or equal to the pre-existing amounts. After review of the improvement plans and drainage calculations it is concluded that the addition of the parking lot and driveway has been detained and designed in accordance with the City of Broadview Heights’ standards. Note: The storm water management requirements of Broadview Heights are very similar to the City of Independence. In addition, the City of Broadview Heights inspects all city owned and privately owned detention basins on a yearly basis and each year the city has reported that the basin was constructed correctly and is functioning per the design intent. It is recommended that the City of Independence receive a copy of the yearly inspection reports of the basin(s) on the church’s property from Broadview Heights Engineering Department. Independence should review the findings of the reports yearly to keep up with any changes in the functioning of the basin at CVC. The photograph at the right was taken looking south standing on Sprague Road looking at Broadview Heights. Here the three streams converge exiting the CVC property and continue north to a 4’x3’ concrete box culvert that runs under Sprague Road and into the City of Independence. Based on our analysis the existing culvert can pass all flows up to the 2-year storm. It is not recommended that the culvert under Sprague Road be upsized it would only have an adverse effect on the downstream properties. Just as the land use changes throughout the Lower Brookside watershed, stream channels also exhibit many different characteristics in different parts of the watershed as well. In areas that are surrounded by development intense land uses, the stream channel exhibits many classic traits of impairment including erosion, under cutting of banks, thick vegetation, sediment deposition and man-made modifications including walled stream banks.


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The photographs shown below were taken in the section of the Lower Brookside Watershed between Sprague Road and Brecksville Road and depict typical conditions found along the stream in that area of the watershed. Conditions such as vegetative overgrowth, deposition and scouring conditions hamper the streams ability to convey stormwater flows and can impair water quality.

The area between Sprague Road and Brecksville Road exhibits critical drainage impediments brought on by a century of impervious surface development and manipulation of drainage corridors. Unfortunately, it is apparent that development within the watershed prior to the mid 1990’s lacked sufficient considerations for infrastructure design, flood damage prevention and long term land use planning. The result is an area prone to nuisance flooding during small rain events and life-threatening structure flooding during large rain events. Since in the mid 1990’s government mandates have promoted increasingly sophisticated and effective stormwater management facilities into the design of new projects. However, the time needed to reverse decades of development which occurred prior to the new mandates through private sector based economic re-development activities would likely extend through the twenty-first century. The residential structures within this area are in very close

Rear yard near 6985 Kingscote looking east.

Rear yard of 6443/6437 Sprague Road looking east

6991 Kingscote looking east 7027 Kingcote looking east


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proximity, both location and in elevation, to the stream channel. These structures occupy the natural floodplain of the stream and as such are susceptible to flooding during large rain events. These structures must also be accounted for in any future improvements in the upper reaches of the watershed because any increase in stream flow rates could cause an increase in the severity and recurrence interval of flooding events that impact these properties. The stream flows under Brecksville Road through a 5’x8’ concrete culvert, also in this location is a 4’x4’ concrete culvert for additional capacity. From here the stream flows northeast through low density larger properties allowing the stream to meander and velocities to slow. Here there are categorized wetlands acting as floodplains to allow stormwater to flood these areas. The stream then combines with the other tributary that picks up drainage from the rear yards of the residents of Montello Road and Dalebrook Road. From here it flows into a channel that runs along Brookside Road through drive culverts of the residences on the south side of Brookside Road. In 2009 the City was awarded grant money from the Clean Ohio Conservation Fund. The City utilized the fund to remove homes and restore the stream corridor at 9050 Brookside Road. The stream in this area is a well defined, steep channel with structures that sit back from the stream minimizing the chances of structural flooding. Before it crosses under Brookside Road to the north the channel combines with streams that drain the rear yards of residents of Dalebrook Road and Dalepoint Road. The channel then crosses under Brookside Road and runs along the north side of Brookside Road where it exits the Lower Brookside Drainage Area. In 2008 the City hired a consultant to create improvement plans that would realign and remove the large amounts of sediment and debris that accumulated from previous storm events that occurred on the north side of Brookside Road. The City worked with the Cuyahoga Valley National Park Service to get memorandum of understanding to have a contractor complete the approved improvement plan.


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Noted Watershed Drainage Issues Upon reviewing the survey questionnaires received from residents within the watershed, site visits by CVE staff, discussions with stakeholders and input received at the public meeting the following concerns were noted within the Lower Brookside Watershed.

o Well documented are the problems in the Sprague Road, Kingscote Park and

Brettin Court area, homeowners not only receive storm water rushing through their yards but have serious structural flooding in their basements. Many residents have done grading around there houses, installed curbing and added gabion baskets to protect their properties and remediate the problem. Nothing has worked and when a large rain event hits this area many residents along the creek flood. The pictures on the next page were taken by Chad and Kelly Cook at 7680 Brecksville Road on August 15, 2011 after a large storm event. The pictures show the amount of water trying to be contained in the channel and the flooding of residents on Kingscote Park and Brecksville Road. These homeowners properties act as a flood plain allowing stormwater spill out of the channel banks and cause both structural and non-structural flooding. Without stormwater management procedures when the older developments on Kingscote Park were built, the undetained runoff from all the impervious surfaces overwhelm the Lower Brookside Drainage System.

6925 Brettin looking east at SR 21 6925 Brettin rear lot looking west

Looking at the rear lot of 7037 Kingscote Rear lot of 7033 Kingscote


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o Many of the residents that live on Sprague Road complain about the huge amount of water running down Sprague Road both from I-77 and Broadview Heights. Residents experience structural flooding from runoff of Sprague Road not being control by the storm sewer system or roadway ditches.

o At 6555 Brettin Court a retaining wall has failed at the pond wall and is

restricting the capacity of the channel. The picture to the right shows the failed retaining wall near the pond on Brettin Court, the wall was built to protect the pond wall but was unsuccessful and the pond is at risk of failure. Also found in the channel near the 6555 Brettin Court pond was a concrete structure that could have been an old headwall that now is abandoned. This structure is also reducing the capacity of the channel by restricting the flow.

o The Brookside Road area also experiences both structural and non structural

flooding. The residents that live on the north side of Brookside Road, east of State Route 21, receive a lot of runoff through their back yards. The main residents that are affected by the non-structural flooding that responded to our survey were the residents at 7816 through 8800 Brookside Road. The residents in this area had a concern that over time the ditches have been filled in and that the existing storm sewer is too shallow to handle all the flow from Brookside Road. Residents in the area also point out that since the demolishing and grading at the St. Maron’s site, the runoff from Brookside Road has increased. The residents on the south side of Brookside Road east of the St. Maron’s site have also experienced flooding from the regrading. Additionally beginning at Dania Drive, the residents that live on the north side of Brookside Road from 7815 through 8703 also experience overland flooding coming from the rear of the yards. The storm system in the rear yards consist of patchwork pipes to convey drainage done by the homeowners over the years. The City of Independence does not hold any easements in the rear of the properties and cannot maintain any of the storm sewer or open ditches.

o On the St. Maron’s site there is a concrete bridge structure that is failing. The structure is in disrepair and is impacting the flow of the existing channel. A picture of the existing structure is to the right.


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o As the stream flows down Brookside Road many residents in the low lying areas have experienced structural flooding numerous times due to the amount of stormwater and the location of the homes relative to the stream channel. Residents in the area have made every effort to divert the stormwater and protect their homes, but during a large storm event there is still flooding damage.

Past Studies of Drainage Issues within the Watershed In late 2006 early 2007 the City of Independence contracted Hydrosphere Engineering to conduct a study on city wide drainage issues. The report looked at five separate areas of flooding which were the Brookside Road/Riverview Road area, the Kingscote Park area, the Dalebrook Road area, the East Pleasant Valley Road area, and finally the Old Rockside Road/Commerce Park area. As part of the Hydrosphere study, questionnaires were handed out, site inspections were performed, analysis was done and recommendations were given. CVE has reviewed the recommendations from the Brookside Road and Kingscote Park area since these two areas are included in our watershed. The Hydrosphere study identified the following flooding problems in the Brookside Road area. Sanitary sewage backup caused by excessive rain water entering the sanitary sewer system, front yard flooding caused by inadequate drainage and pavement buildup of Brookside Road, rear yard flooding in the vicinity of the Marycrest property, rear yard flooding on the north side of the road and out of bank flooding in the vicinity of lower Brookside Road. The report recommended that for the sanitary backup the city should replace and upsize certain runs of sanitary sewer pipe along Brookside Road and to perform smoke testing to identify the sources of the rain water entering the sanitary sewer system. CVE only received two questionnaire responses indicating flooding due to the sanitary sewer in the area. Of the two responses the City of Independence service department installed backflow valves on the sanitary laterals after the August 15, 2011 storm event and each homeowner has not had any problems since. It is unclear if the City of Independence has upsized the sections of sanitary pipes or performed smoked tests in this area, but due to the fact that only two of the flooding cases in the area were due to sanitary back up the upsizing of the sanitary sewer is not recommended. It is recommended that a smoke test be performed in this area if the city receives any additional complaints about sanitary backup(s) or the residents that have had problems in the past and experience sanitary flooding again. The recommendation by Hydrosphere to mitigate the front yard flooding on Brookside Road due to the increase in roadway elevation and the filling in of roadside ditches was to happen when repaving Brookside Road. The existing asphalt surface course should be milled prior to paving. Hydrosphere noted that the front yard flooding was due to the ditches being filled in but the regrading of the ditches is impractical, due to the fact the existing storm sewer would have to be replaced because it is so shallow. The report


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notes that the existing storm sewer is functioning and that lowering the sewer would not be practical due to utility relocations near the ditch. Concerning the flooding of the rear yards of the Marycrest property Hydrosphere recommended that due to the Marycrest site not properly controlling the stormwater runoff that the City of Independence should approach the current land owner to rectify some of the drainage concerns. The same issue still exists today. The City of Independence has regraded a ditch on the east side of the property and home owners in the area have noticed a difference in the rear yard flooding. The flooding of the rear lots of the north side of Brookside Road has been a concern to home owners in the area. The Hydrosphere report recommended that the problem could be solved by installing a perforated subsurface drainage system to outlet into an existing creek. It is also noted that since the city does not hold any easements in the area that the work would have to be performed by the homeowners. Finally, the report touched on the stormwater issues regarding the out of bank flooding in the Lower Brookside area. Analysis was performed by Hydrosphere to verify the correct sizing of the box culvert that crosses under Brookside Road and drive culverts at 8970, 8990, 9000 and 9050 Brookside Road. The results from the analysis indicated that the box culvert would not over top during the 100-yr storm and the drive culverts would not overtop the drives for any storm less severe than the 25-yr. Many alternatives were looked at to reduce the future flooding but the only alternative that can be justified is the removal of the built up sediment from the existing Brookside Road box culvert, which the City has performed twice over the last two years. Also it was recommended to install a debris rack upstream of the drive culvert at 8970 Brookside to help with the debris blocking up the downstream structures and to enforce the riparian setback ordinances to assure storage of materials are not too close to the creek. Hydrosphere also examined locations of upstream detention in the areas of the Marycrest property, a ravine south of Brookside Road and Montello Road and along the stream channel to 7603 Brecksville Road and 7316 Dania Drive. None of the areas provided any significant reduction in the 100-yr storm so none of the sites were recommended for detention.

Conclusions and Recommendations (The recommendations are in no particular order of priority)

o Lower Brookside - Recommendation #1: The City of Independence should

work cooperatively with adjacent communities (Brecksville and Broadview Heights) to implement better stormwater management controls for the watershed. The City of Independence should continue to work cooperatively with Broadview Heights and Brecksville to insure the addition of the maximum amount of stormwater management facilities within the headwaters of the Lower Brookside Watershed as development or redevelopment opportunities arise. The City should work with the neighboring communities in the watershed for any


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stormwater improvements, grant application and for improvements along Sprague Road. Through our meeting with the City of Broadview Heights it is apparent that Broadview Heights is open for discussion for various stormwater improvements within the Lower Brookside Watershed as well as outside those limits. Since there is land available and the headwaters of the watershed are located in Broadview Heights, it would be a good idea for the City of Independence to work with Broadview Heights to build a regional retention/detention basin.

o Lower Brookside - Recommendation #2: CVE recommends that the City of

Independence take immediate steps to remove debris and obstructions along the drainage corridor and establish and on-going maintenance plan for all existing creeks, streams and culverts along the Lower Brookside area and its tributaries.

The accumulation of debris and sediment as well as utility crossings reduce the efficiency at which stormwater can flow through the already impaired stream corridor. The utility crossings decrease the capacity of the channel during most storm events and catch debris causing maintenance issues. Utilities need to be relocated so not to impede the flows within the channels. While removing these obstructions from the creek will not solve the flooding issues common within the upper portion the watershed, it will increase capacity of the channel and thus have an overall positive effect on flood conditions. City forces should undertake efforts to inventory such impediments and work systematically to have them removed. Examples of impediments include the collapsed retaining wall at 6555 Brettin Drive; and a concrete structure in the creek near 6985 Kingscote Park. In addition, many of the streams in the watershed have not been properly maintained and exhibit eroded undercut banks, and excessive vegetation overgrowth. A maintenance program in conformance with environmental regulations should be implemented to address these conditions.

Maintaining flow within stream channels and minimizing obstructions within channels is necessary to offset the impacts of flooding. It is also recommended that the City make efforts to establish a schedule to regularly inspect all portions of the drainage infrastructure, such as yearly and after large storm events, in order to identify newly created impediments that effect system performance and so maintenance activities can be initiated as required.

o Lower Brookside - Recommendation #3: CVE recommends that the City

should continue to notify and educate residents in the Lower Brookside Area of the well known and long standing flooding issues in that area of the community.


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The Lower Brookside Watershed does not contain a FEMA designated floodplain. As a result, several residents noted that they were unaware of the flood risks in the area. CVE recommends that the City establish an outreach program to property owners and renters that own or occupy structures within areas documented to be impacted by consistent flood events. The program should occur on a consistent basis, yearly for example, and via multiple communication channels (mail, email, website, etc.). Information to be distributed could include flood preparedness, eliminate walk out basement(s) in floodprone areas, grade around home to assure the water is directed away from their structure, how to floodproof a structure, safety tips, etc. Given that many of the flood prone areas have flooded repeatedly over the years and since any potential improvement may take several years to develop and be implemented, it is critical that residents are prepared as best as possible to face the risks as they are currently known to exist.

o Lower Brookside - Recommendation #4: CVE recommends that the City consider a program to purchase properties within the watershed that have a documented history of consistent re-occurring structural flooding. Once the properties are acquired the structures should be demolished and projects undertaken to reestablish a natural stream corridor and flood plain with public access open spaces.

It has been documented for at least thirty years that a significant number of the structures built in close proximity to the creek upstream of Brecksville Road have repeatedly endured significant flood events that endanger the health, safety and welfare of the residents of those structures. It has also been documented that the existing stream corridor is impaired due to encroachments, impediments and manipulations. Over the years numerous investigations have noted the limited capacity of the stream corridor and the total lack of sufficient upstream open space needed to implement a regional detention facility. The alternative presented would eventually result in an amenity to the community due to enhanced open spaces, great reduction in flood damage potential, improved water quality, opportunities for additional recreation/educational facilities and enhanced property values. Currently FEMA offers a Hazard Mitigation Assistance Program which allows for the acquisition of real property for willing sellers and demolition or relocation of buildings to convert the property to open space use. Outside funding sources for such a program could possibly include West Creek Preservation Committee and Ohio EPA.

o Lower Brookside - Recommendation #5: CVE recommends that the City work

cooperatively with the property owners on Sprague Road, Brettin Court and Kingscote Park to create a more uniform stream channel as well as reestablishing a floodplain from Sprague Road to Brecksville Road.


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A potential solution to the problem is to widen the channel, eliminate ponds adjacent to the stream, and re-establish the large stormwater flood plain(s) to provide temporary storage. The project could require impacting more than two thousand feet of stream channel. Widening the channel will require permits from the Army Corps of Engineers and Ohio EPA. Because the primary purpose of the stream widening is to alleviate flooding rather than the actual refurbishment of the channel, the project will not qualify as a stream restoration project -- which could have been authorized by Nationwide Permit No. 27 by the Army Corps of Engineers. Instead, the project will require an Individual Permit from the Army Corps of Engineers and a Water Quality Certification from the Ohio EPA. This permit process can take up to 12 months or more. Should the City wish to proceed with this project, the following steps are necessary to obtain the environmental permits: 1. Complete an ecological survey of the project limits (wetland delineation,

endangered species studies, stream channel evaluation, Indiana bat tree study, etc.).

2. Prepare a conceptual design plan for channel modification. 3. Pre-application meetings with Army Corps and Ohio EPA to discuss the

project, its purpose, and to determine if the proposed project can be permitted.

4. Prepare permit application packages and design drawings.


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o Lower Brookside - Recommendation #6: CVE recommends that the City of Independence work cooperatively with the City of Broadview Heights and its residents to install a regional detention basin located in Broadview Heights on the west side of I-77.

The City of Independence will have to purchase property west of I-77 in Broadview Heights, the property that would need to be purchased is located off of an existing paper street that was never built. The City of Independence would have to obtain an agreement with Broadview Heights to purchase land, construct a regional detention basin and also maintain the structure. Through CVE’s stakeholder meeting with Broadview Heights, the City was open to the idea of Independence constructing and maintaining a basin that will ultimately serve the residents of Independence. A sketch of one potential configuration is attached as Exhibit “A”. The basin that is shown is


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approximately 1 acre in size, about 10 feet deep and can decrease the stormwater runoff from the area approximately 60%-85% for the 1-year storm through the 100-year storm while routing roughly 50 acres into the basin. In order to treat that entire area, additional storm sewers and structures would also be included in this project. CVE proposes that a detention basin be installed at west of I-77 between Wallings and Sprague Road. The detention basin would handle flow from the Skyline and Sprague Road area prior to discharging under I-77. Locations for detention, such as the CEI easement, I-77 right of way, the rear lots of several properties, were looked at within the limits of Independence but other factors such as elevation, utility concerns, open space, etc. kept the prospective sites from being feasible solutions for detention. The prospective location of the basin in Broadview Heights will need all the necessary approvals such as from the EPA and Army Corps of Engineers. In addition the project would need to be embraced by both municipalities.

Preliminary Estimated Construction & Engineering Cost: $565,000 plus $150,000 in property and right of entry acquisition


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Proposed Detention Basin in Broadview Heights – Exhibit A


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o Lower Brookside - Recommendation #7: CVE recommends that the City should install a detention basin at St. Maron on Brookside Road. The detention basin will reduce flooding for residences on both the north and south side of Brookside Road. The City must get all necessary easements to access the basin for maintenance, from St. Maron.

CVE put together a preliminary design of two basins that would be located on the east side of the St. Maron site. The first basin (Basin A) located near the road would pick up runoff of Brookside Road and detain the stormwater prior to a controlled release of the water back into the system. The second basin (Basin B) that could be built was sized to detain future additional runoff from possible redevelopment of the St. Maron’s site. This basin should be designed per the actual redevelopment on the site. A sketch of one potential configuration is attached as Exhibit “B”.

Preliminary Estimated Cost: $200,000 *Note: Estimated cost does not included land or easement acquisition.

Proposed Detention Basins at St. Maron – Exhibit B


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o Lower Brookside - Recommendation #8: CVE recommends that the existing

bridge located at St. Maron be removed. The City would need to secure an easement for access to the structure for demolition.

Such restrictions can lead to reduced flow capacities within the channel and thereby excessive water pooling in the street and unpredictable overland drainage. It is also recommended that the City make efforts to establish a schedule to regularly inspect all portions of the drainage infrastructure, such as yearly and after large storm events, in order to identify newly created impediments that effect system performance and so maintenance activities can be initiated as required.

Preliminary Estimated Cost: $25,000

o Lower Brookside - Recommendation #9: CVE recommends that the City of Independence work cooperatively with the City of Broadview Heights and Brecksville to improve Sprague Road drainage.

Many of the residents CVE spoke to that live along Sprague Road have complained about flooding coming from the runoff of Sprague Road and I-77. The reprofiling of the cross section as well as the addition of concrete curb and new storm sewers will improve drainage and keep runoff from Sprague Road within the roadway and outside of the yards. Preliminary Estimated Cost: $175,000

o Lower Brookside - Recommendation #10: CVE recommends that the City of Independence work with the homeowners along the north side of Brookside Road to help alleviate the chronic rear yard flooding. The residents from 7707 Brookside to 8703 Brookside experience large amounts of rear yard flooding. The storm sewer that runs in the rear yards of these addresses is a piece meal system that have been constructed by previous homeowners and the City does not have any recorded easements in the rear yards.

The City of Independence could perform the design and construction throughout this area to elevate the constant standing water and rear yard flooding. It would be our recommendation to perform this work through an assessment of the resident of the improved lots. After the improvement is completed, CVE also


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recommends that the City help the homeowners along Brookside implement a homeowners association for all the property owners between the above referenced addresses on the north side of Brookside Road. The association will be an avenue for the residents themselves to implement future maintenance and engineered solutions for the flooding problems that plague those properties.

o Lower Brookside - Recommendation #11: CVE recommends that the City look into areas to use best management practices (BMPs) that will allow rain fall to be absorbed into pervious surfaces like bio-retention swales and porous pavement.

These areas shall specifically be for bioretention in public right of way on Montello, Dalepoint and Dalebrook Roads and for the installation of porous concrete at the cul-de-sacs of Montello, Dalebrook and Dalepoint Roads. These areas are locations east of SR21 that are tributary to the lower brookside drainage area. The installing theses BMP’s the large amount of impervious area could be treated and absorbed into the soil during the 1-year and 2-year rain events and reduce the amount of discharge into the ravines.

The distribution of existing impervious areas (i.e., streets, rooftops, driveways, businesses, parking lots, etc) and the associated stormwater infrastructure presents multiple opportunities to divert stormwater runoff into appropriately situated best management practices (BMPs) that promote infiltration.


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Bioretention Cell Sizing and Range of Cost* Contributing Drainage Area

(acres) Size of Cell (sq.ft.) Range of Cost

0.25 328 $6,560 - $9,840 0.50 656 $13,120 - $19,680 0.75 984 $19,680 - $29,520 1.00 1312 $26,240 - $39,360 1.50 1468 $29,360 - $44,040 2.00 2624 $52,480 - $78,720 2.50 3280 $65,600 - $98,400

*assumes Runoff Coefficient (C) value of 0.80; Saturated Hydraulic Conductivity (Ksat) value of 1.00; planting soil depth of 30-inches; and a maximum ponding depth of 12-inches

Preliminary Estimated Cost Porous Pavement: $16.00/SF

OTHER RECOMMENDATIONS

o City Wide Recommendation #1: CVE recommends the City of Independence adopt a more stringent stormwater ordinance regarding certain requirements for any residential or commercial improvements within the city depending on what type of project, either development or redevelopment that would be proposed.

An example of the ordinance would include for any earth disturbance over 5,000 sq. ft., it would be required for drainage plans to be submitted and approved. The ordinance also would mandate that such projects adhere to stormwater peak rate control requirements formulated by the city. If any earth disturbance is over 1 acre, the requirements for 5,000 sq. ft. disturbance would apply as well as additional requirements items such as, groundwater recharge, water quality aspects, stream bank erosion controls and that an Erosion and Sediment Pollution Control Plan to be submitted to the City Engineer.

The proposed ordinance would also include requirements for projects that increase impervious surfaces as well. If the additional impervious surface area for the proposed project is over 501 sq. ft. but less than 1,499 sq. ft. the City could require that the developer adheres to the drainage plan requirements, and groundwater recharge requirements spelled out by the City. For areas that are increasing the impervious surface greater than 1,500 sq. ft., the requirements for the smaller areas would still apply as well as the addition of water quality requirements, stream bank erosion requirements and stormwater peak control requirements.


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o City Wide Recommendation #2: CVE recommends that the City revise the following ordinances.

A. CVE recommends revising the applicable section(s) of the city’s building

code that governs gutters and downspouts to allow for downspout disconnections for the purpose of installing infiltration BMPs, rain barrels, and daylighting downspouts. The building code sections referred to as Basic Standards for Residential Occupancy; Maintenance of Roofs, Gutters and Downspouts, is typically an appropriate section to incorporate these revisions. Examples of language revisions adopted by nearby communities are readily available.

B. Chapter 1354 – Riparian and Wetland Setback Requirements

This chapter only addresses Category 2 & 3 wetlands (as determined via the Ohio EPA’s ORAM assessment tool) and their respective buffer widths of 75-ft and 120-ft. Although this is consistent with regional model ordinances, the City should consider amending the ordinance to include Category 1 wetlands with an associated minimum buffer width (e.g., 25-ft). Although Category 1 wetlands generally provide little habitat of significant value and are typically comprised of no more than a few plant species, they still provide a significant flood control function.

C. Chapter 1181 – Off-Street Parking and Loading Requirements

Although a portion of this chapter has been updated as recently as 2009 (1181.061), the vast majority has not been updated since 1962. CVE recommends the City undertake a process to update parking codes so they offer more flexibility with regard to ultimately reducing stormwater runoff volumes. At a minimum, the review process should consider updating the city parking codes for the purpose of reducing impervious cover, minimizing maintenance costs, and facilitating the construction of more efficient and aesthetically pleasing parking areas. Specific areas of consideration should include: • Review of local parking requirements with an evaluation of the following

factors o Local parking demand o Building types and sizes o Surrounding land uses o Current and expected population o Potential for additional commercial, industrial and institutional

development • Improve parking lot design

o Establish minimum landscaping requirements o Incorporate compact car spaces o Minimize stall dimensions o Require the use of pervious surfaces in overflow and other low

traffic parking o Consider the most efficient dimensions of entrances, aisle ways,

and parking spaces


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• Adopt parking maximums (instead of minimums), based on the area of a specific land use and restrict the total number of spaces that can be constructed for a particular use

• Require shared parking where appropriate • Allow land-banking for future parking spaces, should the need arise

Information above adapted from a parking requirements fact sheet entitled,

Parking Lots, Impervious Cover & Storm Water, by the Chagrin River Watershed Partners, Inc.

o City Wide Recommendation #3: CVE recommends that the City update

Chapter 1381 regarding Long-term BMP Maintenance.

There are several components that work in concert to ensure the long-term viability of a post-construction BMP maintenance program. CVE has reviewed Chapter 1381 – Controlling Post-Construction Water Quality Runoff , to assess which components could be enhanced or added. 1. Require submittal of a standardized, customizable Inspection and

Maintenance Agreement (I&MA) for all sites on which there are permanent post-construction water quality and/or water quantity stormwater control measures. The I&MA binds perpetual maintenance responsibilities for the BMP(s) to the current owner and all subsequent owners of the property. A fully executed I&MA would serve as an “owner’s manual” and, at a minimum, would incorporate a full set of the approved engineering drawings, all maintenance plans and all easement information. At this time, Chapter 1381.08(h) only requires a stand-alone document be provided that includes, “Long-term maintenance requirements and schedules of all BMPs for both the construction and post-construction phases of the development…” a. Include the following language within each I&MA - The City of

Independence is authorized to enter upon the property and to perform the corrective actions identified in the inspection report if the landowner(s), organization, or municipality responsible for maintenance does not make the required corrections in the specified time period. The City of Independence shall be reimbursed by the landowner(s), organization, or municipality responsible for maintenance for all expenses incurred within 10 days of receipt of invoice from the City.

2. Require each property owner to post a cash bond with the City that covers the average annual cost to maintain the BMP(s). The cost estimate should be reviewed and approved by the City.

3. Ensure owners/operators of post con-BMPs perform the required annual maintenance inspections during a wet weather event and only complete a dry-weather inspection as necessary per the findings of the wet-weather inspection (e.g., certain design features may initially be submerged).

4. Provide model maintenance plans for a variety of post-construction BMPs for the purpose of ensuring consistency from site to site.


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5. Clearly specify the minimum content that must be provided per type of BMP, as part of each annual inspection report submittal.

6. A qualified representative of the City should periodically conduct a follow-up inspection after receiving annual written inspection reports provided by owners/operators. These should be completed during wet weather events for the purposes of ensuring inspection reports provided by the owners are accurate.

7. Provide a qualified representative of the City to inspect the installation of all design features of each applicable BMP, regardless of being situated in or out of a public ROW.

o City Wide Recommendation #4: CVE recommends that the City find ways to

put into practice best management practices (BMPs) that will infiltrate flow generated by existing impervious surfaces.

Because of the inability to absorb water, existing impervious areas account for the greatest amount of runoff on a per acre basis. With a few exceptions, runoff generated by existing impervious surfaces throughout the watershed is currently being piped directly into streams without any opportunity to infiltrate. Therefore, it is easy to surmise that a focus on promoting the infiltration of runoff generated by impervious surfaces can assist in reducing flood occurrences. The distribution of existing impervious areas (i.e., streets, rooftops, driveways, businesses, parking lots, etc) and the associated stormwater infrastructure presents multiple opportunities to divert stormwater runoff into appropriately situated best management practices (BMPs) that promote infiltration. These BMPs can be situated within the public right-of-way (ROW) or entirely on private property. The following points must be considered when situating BMPs within the public ROW: • Performing long-term maintenance activities would be the responsibility of

the City, although each would be easily accessible. • Existing utilities and existing storm infrastructure inverts will present the

greatest limitations. • Landowner by-in will be important to the overall success, primarily due to

aesthetics. • Runoff generated either by public streets or privately-owned rooftops and

driveways can be diverted. However, the latter would require allowance for disconnecting downspouts via a building code amendment.

• Existing streets can be retrofit by placing BMPs along a slope or within a sag in the street, as long as tree lawn areas are at or above grade.

The following points must be considered when situating BMPs on private property: • Landowner participation would be voluntary.


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• Participation could be encouraged by the City through financial incentives (e.g., cost-sharing to offset initial investment and/or reductions in stormwater utility fees.

• Runoff generated by privately-owned rooftops and driveways can be diverted. This would require allowance for disconnecting downspouts via a building code amendment.

• BMPs can be situated in front, side or rear yards. • A detailed assessment parcel-by-parcel would be necessary to determine

appropriateness (no negative impact to on-lot and off-lot structures/landscaping).

• BMP options include: o Convey downspout discharge or driveway sheet flow into rain gardens,

which are either turf-covered or traditionally landscaped with perennial flowers/shrubs/trees

o Convey downspout discharge or driveway sheet flow into dry wells o Daylight existing downspouts into existing vegetation

• If long-term maintenance responsibilities are assumed by the City, the BMP would require an easement. But if they are assumed by the landowner, a binding agreement between the landowner and the City is recommended.

Retrofitting residential neighborhoods with stormwater BMPs is an action many landowners are unfamiliar with. As a first step in initiating such an effort, the City should consider conducting a survey of stakeholders so they better understand landowners’ current level of awareness regarding the purpose of these types of BMPs, how they would be impacted by them, and whether or not they would be accepting of them. After analyzing responses, the city can then formulate a campaign to overcome these obstacles and ultimately maximize by-in and participation. Furthermore, constructing one or more demonstration BMPs will provide opportunities for community involvement and serve as a real-world visual for stakeholders, both of which could increase by-in. CVE also recommends the City consider allowing homeowners to implement rainwater harvesting systems (e.g., cisterns and rain barrels). Their purpose is to provide a reliable source of non-potable water by capturing and storing roof runoff to be used for activities including, but not limited to, landscape irrigation and car washing. Although they are more appropriately classified as water conservation measures, and therefore should not be counted on to significantly reduce total runoff volumes, they do provide homeowners an option from which they can directly benefit, and by default, will intercept and reuse a small volume of runoff that would otherwise be piped directly to a stream.

o City Wide Recommendation #5 : CVE recommends the City develops and

implements programs that encourage tree-planting on both private and public property. A healthy urban forest promotes increased infiltration and the capture and storage of rainfall within the tree canopy.


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o City Wide Recommendation #6 : CVE recommends that the City Develop and implement a stormwater utility to provide an equitable and uniform funding stream to maintain and improve the common system of public drainage. One of the most basic yet important functions of city government is to protect the health, safety and welfare of its constituents through the management of water in all of its forms. Municipal entities facilitate systems that provide clean drinking water, carry away wastewater and manage stormwater drainage. Each of these systems require both a broad backbone of infrastructure as well as individual branches unique to each parcel of property within the city in order to provide the various services to the residents. These systems also require consistent maintenance, planning and improvements in order to work in an effective and efficient manner. Until relatively recently most municipalities recouped the costs of service for drinking water and the removal of wastewater through direct user fees yet shouldered the monetary burden of stormwater drainage via general revenues, assessments or targeted tax measures. However, there is a growing trend among local governments to assess equitable direct user fees for stormwater drainage as well. A Stormwater Utility provides a method to charge a fee on residential and non-residential properties based on the specific characteristics of the property and thereby its use of the common stormwater drainage system. Just as consumers of the potable water supply pay a charge based on the amount of water they consume, property owners within a Stormwater Utility’s service area would pay a fee based on the characteristics of their properties that impact how much stormwater the public system of drainage must convey. A public system of drainage can consist of many different types of conveyance and management facilities. Examples of conveyance mechanisms include roadside ditches, storm sewer systems, drainage swales, creeks and streams. Types of management facilities can include detention basins, retention ponds, water quality basins, rain gardens and wetlands among others. Over the last century years two distinct trends have been converging to the detriment of local governments. The first trend is the increased development of land for residential and commercial purposes. Land development brings about many changes to a community. Benefits of land development can include an increased tax base, higher property values and conveniences to the residents. Unfortunately, the same development can cause increased amounts of stormwater runoff, a lessoning of water quality, increased traffic congestion, increased demands on city services and on-going infrastructure maintenance responsibilities that compound over time.


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The second trend is the increase of state and federal regulations that impact the extent and function of the common system of drainage. Federal and state governments across the Country have consistently increased the extent of regulatory oversight concerning water resources. The increased amount of water pollution regulations has enabled great improvements in all aspects of water quality to be achieved but with substantial costs. Recent federal and state mandates relating to stormwater have placed a significant financial burden on local governments in particular. These mandates, such as the Phase II Program are requiring municipalities to expend financial resources to inspect, inventory and improve their stormwater infrastructure and governing ordinances. Unfortunately, neither the federal or state governments have brought forth significant funding sources to offset those costs. As the detriments of development, compounding maintenance responsibilities and regulatory mandates impact upon local governments, funding sources that are targeted, uniform and consistent become necessary to provide an effective and efficient public system of drainage. In an effort establish a consistent and equitable funding stream, municipalities throughout northeast Ohio and across the country have already established or are investigating the merits of a Stormwater Utility as a way to pay for the short term and long term needs of the public system of drainage within its municipal boundaries. The concept of municipalities charging a user fee rather than assessing a tax is not new. User fees for the provision of trash collection, drinking water, wastewater treatment, electricity and natural gas by municipalities is quite common throughout the nation. Each of these systems charge a fee to its users based on the amount of usage. A stormwater utility is the same concept; users (property owners) of the public common system of drainage are charged a fee based on the demands that their property places on the system. Currently there are approximately 1000 stormwater utilities established throughout the United States. All parcels of land produce stormwater runoff that must be managed by the public system of drainage, including undeveloped parcels. However, as land is developed and covered with impervious surfaces, such as pavement and rooftops, additional demands are placed on the public system of drainage. Additional demands are created because impervious surfaces greatly reduce the natural infiltration and absorption of stormwater runoff into the natural environment. As a result, areas of impervious surfaces have been shown to generate greater volumes of stormwater runoff, increased peak runoff flow rates and higher concentrations of suspended pollutants. These additional demands must be accommodated by increased program management needs, infrastructure improvements and/or additional maintenance to the public system of drainage in order to protect the health, safety and welfare of the community.


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o Other Recommendation #7 : CVE recommends that the City include a credit

program in any stormwater utility developed so to incentivize innovative and effective stormwater management initiatives

For the purpose of reducing stormwater runoff volumes, it is recommended that the City embark in an effort to provide incentives to homeowners and businesses in an effort to reduce runoff volumes. An effective and proven means of accomplishing this is through the development of a credit system associated with the stormwater utility. Not only would the implementation of a stormwater utility serve as a source of revenue for a comprehensive stormwater management initiative, but more importantly it can be utilized to create a financial incentive for customers. By implementing stormwater best management practices that serve to reduce runoff volumes and/or runoff flow rates, customers would be eligible to earn credits that would reduce their overall stormwater utility fees. Stormwater credits can be earned as a result of the construction, operation, and maintenance of privately owned stormwater management practices that reduce the contribution of stormwater to the City's collection and conveyance systems.

Impervious Area Stormwater Credit (all hard surface areas) Gross Area Stormwater Credit (entire parcel)

Depending on the types of stormwater management practices implemented on a site, a property may be eligible for both classes of credits. The maximum credits a property can receive cannot exceed 100% of a property’s gross area and/or impervious area. Any property that is able to achieve a maximum credit is still subject to a monthly minimum charge.

Impervious Area Credit An individual or combination of stormwater management practices must collect and treat the first inch of runoff from impervious areas draining to them. Partial credit is not granted for a property if the practice(s) address only a portion of the first inch of runoff. Partial credit is available for properties which fully manage the first inch of runoff from a portion of a property’s total impervious area. The square footage of impervious area credit approved is equivalent to the square footage of impervious area that is collected and treated.

Gross Area Credit Two options are available to property owners to receive a gross area credit, and owners may apply under one or both options.


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However, the total gross area credit may not exceed 100% of a property’s gross area.

Option 1: GA Credit Based on NRCS-CN Under this option, the property owner must demonstrate a Natural Resource Conservation Service Curve Number (NRCS-CN) of 86 or less for the entire area within the property boundaries. The Curve Number (CN) represents the runoff characteristics for a particular soil and ground cover. A 7% reduction from the gross area charge is applied for every whole number below 87; therefore a CN of 72 may yield a maximum of 100% gross area credit.

Option 2: GA Credit Based on Attenuation of Peak Rate of Runoff Under this option, the property owner must demonstrate a stormwater management practice that reduces the peak rate of runoff associated with a 2-yr storm. A 100% credit can be achieved by reducing this runoff rate to less than or equal to the one-year peak runoff rate associated with the property’s site conditions that existed prior to implementation of applicable stormwater management practices.

A class of credit expires four (4) years from its effective date. An applicant must submit a credits renewal application to renew the stormwater credits. Regular inspection and maintenance of every applicable stormwater management practice must be performed to maintain credit eligibility, and this information must be verified by a qualified registered professional.

There are a number of sources for grants and low-interest loans available to provide funding for projects that support the recommendations contained within this report. Although the primary focus of this watershed study is to address the reoccurrence of flood events, numerous funding opportunities exist that are centered around in-stream and/or riparian habitat improvements. It must be understood there is a direct correlation between the proper management of flood waters and healthy floodplains and stream channels. Therefore, seeking grants that place a priority on habitat improvement should not be discounted. Lastly, it is important to remember stakeholders impacted by this study may not be familiar with many of the recommendations that are presented within it, specifically the various on-the-ground best management practices discussed. Developing and implementing a successful education campaign is a critical component of maximizing stakeholder by-in. Therefore, grants that solely or partially support watershed-based education initiatives should also be considered.


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The Ohio EPA maintains a comprehensive list of funding sources on their Office of Environmental Education web page. Go to the following link (scroll down to “Resources for Grant Seekers”): http://www.epa.ohio.gov/oeef/grantee_resources.aspx

APPENDIX A

lower brookside drainage study - independence, ohio

Documents