Stormwater Management Intergovernmental Agreement – York Commons Park
Commissioner Graf made a motion that the Board of Park Commissioners approve the intergovernmental agreement between the City of Elmhurst and the Elmhurst Park District for the construction, operation, and maintenance of stormwater improvements in York Commons Park, Elmhurst, DuPage County, Illinois and authorize the Park Board President to execute said IGA. Commissioner Pelosi seconded the motion.
Executive Director Rogers reported on the stormwater committee meeting held on December 9 in City chambers which had five residents in attendance of which four spoke during public comment. At the committee meeting, all five sites under consideration were discussed. There was general agreement amongst the two entities concerning the conversion of the Golden Meadows site per the Park Board’s proposal. The Golden Meadows proposal requires official consideration by the City's Public Works Committee, which, according to the City Manager’s public comment at tonight’s meeting, is forthcoming. The District’s stormwater subcommittee committed that once an IGA for Golden Meadows has been approved, the Park District will approach IL Dept. of Natural Resources (IDNR) regarding the concept of escrowing City funds while working towards acquiring replacement property to help expedite the provision of stormwater relief.
Regarding the other three parks in consideration including East End Park, Crestview Park, and Wild Meadows Trace, City officials suggested the Park District consider foregoing replacement and compensation for those sites and instead work with the City to either ask IDNR to make an exception to the policy of restricting mediation of off-site stormwater to OSLAD funded sites or that both entities (City and Park District) work together to identify ways to facilitate both the construction of stormwater basins in conjunction with improvements to the park. The District’s subcommittee requested the City respond to the District’s November 19 proposal in writing and submit any proposed new approaches for the Park Board to consider. As of December 16, the District has not received anything from the City specific to the sites.
Regarding York Commons, on December 7, as part of its consensus agenda, the City Council unanimously approved the Public Works Committee report containing the major terms relating to York Commons proposed by the Park Board. Rogers reviewed highlights of an IGA with the City to include an 11 acre foot detention basin on the west lobe of York Commons Park. The IGA included two attachments that will become exhibits of the IGA. One attachment was the detention basin maintenance staff schedule and the second a preliminary grading plan showing where the site will be located and how it will work.
The first paragraph of the IGA broadly covers the use of the west portion of York Commons Park along York Road for stormwater detention with the installation of an automated shut-off valve to the stormwater basin from Crescent Street to prevent the basin from taking on water exceeding the 100-year elevation.
Paragraph two extends the Park District’s lease of the maintenance facility garage through February 29, 2108 to coincide with the length of the lease for Fire Station No. 2 in York Commons Park. It also calls for a perpetual agreement allowing the City an easement for maintenance of the detention and temporary construction easement to allow the City access to the park to build the basin. The proposed easements will be part of the exhibits to the IGA; attorneys are still working on language to include in the final IGA.
Paragraph three calls for a review of the plans and specifications for the project at predetermined intervals and at percentages of completion. The review milestones were developed with assistance from V3 engineer Greg Wolterstorff using industry standards. A clause calling for mutual agreement of the final plans and specifications between both agencies is included.
Paragraph six involves the coordination of the construction schedule with the two entities working together to figure out what is the best timing and phasing to work on the construction. Coordination discussions have already begun.
Paragraph seven covers the demolition of facilities. Should it be necessary for the City to demolish any improvements in the park, the District will receive advanced notice of such. Also, included is required videotaping of the site before work begins to obtain a baseline of existing conditions.
Paragraph eight calls for restoration of the park by the City after the detention basin is completed and the replacement of trees on a 1-to-1 inch basis, along with the Park District’s option to elect for replacement value for some of the trees rather than having new tree stock installed. Commissioner Graf stated that the tree replacement clause is the Illinois Standard from the Illinois Arborist - Diameter per Breast Height (DBH), which is the diameter of the tree at 4.5 ft. above the ground. Tree species fall in a different category on a percentage. As an example, ash trees are considered scrub trees. Executive Director Rogers stated that one of the sub-points in that paragraph covers trees that will not be evaluated for reimbursement such as diseased trees or those that should otherwise be removed, i.e. ash trees due to emerald ash borer infestation, American elm diagnosed with Dutch elm, and dead, dying, declining or severally damaged trees. The City has already conducted a preliminary tree inventory, which will be part of the videotaping.
Paragraph nine discusses environmental testing and remediation by the city. In this paragraph, the City has the ability to void the IGA in its entirety if the site contains environmental contamination or hazardous material(s). Should the City determine not to move forward after contamination is discovered, the entire IGA, including the extension of the maintenance garage lease could be terminated as the District does not expect to receive something without an exchange of services.
In response to Commissioner Spaeth’s question regarding the District’s liability should contaminates be found, Executive Director Rogers stated that contamination would be discovered during soil boring testing prior to construction. The ground will still be capped. As it is District property, the District would decide what steps to take from there. If the City does discover something; they have the option to move forward by developing a remediation plan, which both parties agree to. Contamination may be found to be minimal enough to move forward, but the City has the option to say no and not move ahead. Should the testing result in no contamination, but further digging finds contamination, the City must decide to remediate or back away. It is District property; therefore, the District would need to determine if it needs to be re-capped or remediated.
Executive Director Rogers continued with his review of the IGA where paragraph ten covers the maintenance and repair of the stormwater improvements by the City. The maintenance plan was developed with V3 engineer Greg Wolterstorff using an outline from another detention site. All of the tasks and the frequencies have been evaluated. The tasks were sub-coded to denote the responsible party both for short and long-term maintenance.
Paragraph eleven details the indemnification/hold harmless language and insurance requirements. The entire agreement has been fully vetted and developed with District attorney Andrew Paine and City attorneys.
Paragraph twelve speaks to termination with two provisions. The first is language allowing the City to terminate the IGA prior to construction. The second states that the Park District can terminate the IGA if the City does not begin construction within two years extended from the initial stipulation of one year. This should not be an issue as the City has every intention to move forward as quickly as possible. In the case of either of these two terminations being enacted, the extension of the maintenance facility will remain in effect. Once this agreement is approved by both bodies, the extension of the maintenance facility is in effect. It would not be the case if environmental contaminates are found and the City terminated the agreement for that reason.
Commissioner Ennis inquired as to why the District is requiring an automated shut-off valve when both engineering firms stated it is not needed especially when electronics do fail or freeze. He stated he was not for the shut-off valve being part of the system.
In response to Commissioner Ennis questioning the inclusion of a shut-off valve, Commissioner Spaeth stated that the shut-off valve was always part of the original plan. When the District began discussions a year and a half ago, it presented its proposal to the City and the recommendation at the time was for the west lobe and included the shut-off valve. The shut-off valve was always included regardless of which lobe (east or west lobe) or both. In the District’s subcommittee discussions with Burke, it became apparent that the incremental cost of the Madison School and York Commons sites were much more costly then infrastructure improvements. Even though hundreds of thousands of dollars could have been saved with infrastructure improvements, the Park District recognized the small impact a detention basin could have on a number of homes. For that reason, the Park District proposed to allow the use of the west side of York Commons instead of relying solely on infrastructure improvements as the solution.
In addressing increased costs associated with the shut-off valve, Spaeth noted infrastructure improvements would have been the least expensive route. Additionally, the District waived the City’s proposed recreational amenities saving an estimated cost of $200,000. During discussions regarding the east lobe and west lobe of York Commons, the City proposed Cayuga coming into the lobes and later added Crescent Street. Many scenarios were discussed including what could happen in the future. After much discussion, the District proposed an 11 acre foot basin for the City to put whatever water they wanted - a 100-year, 500-year, etc. based storm event. Although the District would not be responsible for managing the detention, being part of the solution was important with the stipulation of a shut-off valve to protect and provide safety to the residents on the west side of York Street. In considering changes for the future, a 500-year storm event today may not be graded as such in the next 5 or 10 years. Fifteen years ago, storm frequencies and intensities were considerably less, thus it is uncertain if rain events will become progressively worse.
Commissioner Spaeth noted the continued development of the housing stock exacerbating the problem by creating increased impervious surface. The increased size of homes being built continue to stress the system. Therefore, whatever the static heads are from Crescent Street driving water into the detention, the levels can get higher and higher. The engineering work to date is valid, it is the unknown severity of future storms that are a concern. A shut-off valve is a necessity to protect those living near and going through the major thoroughfare of York Street. York Street is were fire trucks exit York Commons and is the route to the hospital. A massive overflow of the detention, at some point in the future, would be detrimental.
In regards to the failure of the valve, engineers design so that the failure mode is an acceptable mode of failure. The valve is going to be open 99.99% of the time, it will never be closed unless the basin is filled. When the basin is full, it will automatically shut the valve. The failure mode is open. There should not be a situation during a power loss that the valve is somehow going to cause something worse then what would happen without the valve at all. The valve is an added safety factor even with its cost. The Park Board has vetted this out to the nth degree.
President Ubriaco agreed with all points made by Commissioner Spaeth and stated that the last 500-year flood was on June 23, 2010, which is the model being used to determine the impact of internal flooding and the efficacy of a shut-off valve, but the reality is that the world has changed a lot since then and that model would look very different today. One thing that remains constant is that there is more impervious surface not less so there is greater exposure for overflow. It would be horrible if an overflow caused the neighborhood pain. It is extremely dangerous to flood York Street as it is a lifeline to and from the hospital. It is a heavily traveled road.
Commissioner Morissette-Moll stated that the Park District is acting as a diligent neighbor and is not trying to increase the complexity of the City's storm management and advised the City that a closer pulse be kept on the rampant building of mansions that are consuming the majority of earth.
Commissioner Graf agreed that a shut-off valve is necessary from the standpoint of the people living near the proposed basin on York Road. The homes directly across the street are below grade as well as the people downstream. York Road is a thoroughfare and that is where the water travels, down through there to Washington Street to McKinley. The Madison School detention basin is going to help Washington Street; the York Commons basin will help a few homes on Washington and down that corridor. The bigger piece is the City’s commitment to the southwest infrastructure improvements, which the IGA mentions the City’s full intentions to complete the comprehensive stormwater plan. When the infrastructure improvements are made, the York Commons detention basin could potentially be downsized. Commissioner Graf stated he looked forward to getting the project underway to provide relief to folks flooding on Crescent.
President Ubriaco stated that she was satisfied with the IGA and pleased with the work completed on all sides. The City’s plans to install infrastructure improvements could make this stormwater basin obsolete and unnecessary. In response to President Ubriaco’s inquiry whether the IGA addresses the removal of the stormwater basin, Rogers stated the IGA does not address the removal. Commissioner Spaeth stated there was some discussion about removal that could still be addressed in the future, but for the sake of getting shovels in the ground the IGA is thorough. President Ubriaco stated that she would not want the District to be left with a basin when it no longer becomes necessary and questioned if there may be some adaptive reuse for stormwater basins. She did not want the City to hold the land use in perpetuity if it were not necessary.
Executive Director Rogers added that at this point, it is uncertain what the City would do to make the basin unnecessary. At some point, should the City deem it unnecessary with a shut-off valve that has operational and maintenance costs, the City would want to take it off line. Commissioner Spaeth added that both the City and Park District have established a great relationship and there will continue to be many more projects in town to work on and help each other out. The District will always strive to do what is best for the community; the IGA exhibits the District’s good intentions. It is more important to get shovels in the ground and move forward with some level of trust for the future. Commissioner Graf added that the committee did discuss provisions for bona fide uses similar to School District discussions regarding educational uses, where the Park District would give the City a one-year notice.
President Ubriaco asked about toxic material buildup and the monitoring of such that may pose a hazard to park users. Executive Director Rogers stated that the maintenance tasks schedules covers annual inspections for sediment and accumulation and on an as-needed basis, removal of sediment accumulation. If required, a professional engineer will carry out an inspection upon identification of severe problems. Should other soil concerns exist, the District can require the City to bring someone in a professional engineer and identify the problem and look at a way to remediate.
Commissioner Pelosi and Kies supported a shut-off valve as part of the detention basin.
In Commissioner Spaeth’s visit to pump houses on the creek and to the wastewater treatment plant, he saw many pumps and found some all over the city. In this particular case, the District can have a manual closer valve not just a motorized valve. It all depends on the engineering of the basin for the failure mode and what safety precautions need to be in place. The fact remains that water from a 5-year storm, 100-year storm, or infinite-year storm can be stored there, but when it is full it is full. That is what was agreed. As there were no further comments or discussions, the Board was polled. Ayes: Commissioner Pelosi, Ennis, Graf, Kies, Morissette-Moll, Spaeth, and Ubriaco. Nays: None. Motion passed unanimously.
