Stormwater Commission

Stormwater Commission Meeting Summary Tuesday August 11, 2020 Members Present: Fred Kudert, Steven Vinezeano, Thomas Powers, Andrew Vitale, Joseph LoVerde, Fred Braun, Chuck Ostman , and Rich Wlodarski . Residents in attendance: Rosemary Palicki, Karen Dimond, Jessica Bertucci, Alex Others in attendance: Jeff Wickenkamp, Hey and Associates; Jack Grana, Village of Niles; Steve Maney The Stormwater Commission meeting convened at 8:00 a.m. in the Council Chambers at Village Hall and via Zoom Virtual meeting software. Resident Concerns: Petition – 7600 Block between Oketo and Odell Ave near Howard Street The residents for the area bounded by Oketo, Odell and Howard presented a petition to the stormwater commission. The petition was previously presented to the Board of Trustees and referred to the stormwater commission. The nature of the problem is a rear yard drainage issue without a proper overland flow route out of the back yard. The downstream sewer has known capacity issues. The resident’s engineer proposed a solution to problem with a catch basin at an estimated cost of $25,000. Hey looked at the model of the sewer system to evaluate the solution. The existing sewer is a 12” combined sewer. The sewer analysis indicates that the sewer does surcharge during certain storm events. The Village engineer agreed that the catch basin would help with the drainage issue, however the expectation should be that the flooding would not be resolved 100%. A restrictor would be required due to the downstream flooding. The duration of flooding would be reduced but likely not the extents of flooding. It was pointed out that the Village is in the process of implementing a rear yard drainage assistance program. If the $25,000 was paid from the budget line item for rear yard assistance was used, the project amount would use half of the budget line item. The Village Engineer indicated based on the petition, the project would qualify for the $4000/50% cost share program. The Village board was set to consider the drainage assistance program at the next Board meeting. The chair asked how the problem could be completely resolved. The Village Engineer indicated that one home could be eligible for overland flood program to flood proof their home. A long term solution to completely resolve the flooding in this area would require a conveyance and reservoir system which are difficult to construct in the right-of-way. The stormwater master plan does not include a project to serve this area, so we don’t know what a long term solution would be. The preliminary indication based on surface grades is that the problem would be difficult to fully resolve. The $25,000 solution would improve drainage but not completely resolve flooding. Commissioner Kudert asked how many of the 26 storms in the petition would the CB solution resolve flooding for? The engineers responded that they had not studied the sewer on a storm by storm basis, but we know in general that small diameter combined sewers are a problem throughout town. Chair LoVerde asked whether a project from the cost share program would benefit the residents. The Village Engineer concurred that the basin would improve the situation for small storms and that $25,000 is a high cost for a homeowner to incur. The program was drafted to allow individual homeowners to apply but the concept of multiple homeowners applying for one expensive project has not come to a final resolution. The original petition was from the May 25th and the Board expects a recommendation from the Stormwater Commission about whether the Village should fund the project. Jessica Bertucci provided public comments. She reiterated the major petition points of the Village should pay for the design, installation, and long term maintenance of a solution. The area floods during low intensity storms and there has been recent structure damage. The residents opinion is the flood area is a retention pond. The independent engineer who supported the petition was Steve Maney. The Village Manager asked how Ms. Bertucci felt about a solution that only reduces duration. Ms. Bertucci indicated she understood that and felt the CB would still be a benefit. The Village Manager asked if we could study the sewer impacts in more detail. Hey indicated that they actually studied a similar case and previously presented their findings. Unrestricted yard drainage connection to the combined sewer does have impact to adjacent properties. The general policy decision that resulted from that was that all yard drainage connections to the combined sewer should be fitted with a restrictor. The restrictor would provide a drainage improvement but would not provide a flood benefit to structures in a large storm. Steve Maney provided public comments. Mr. Maney clarified the petition was incorrect and they are not looking to eradicate the flooding but they are looking to improve the drainage for low intensity storms. He mentioned that there was a legal review of the issue. He felt this was a municipal issue and not a homeowner issue. Mr. Maney had some questions about the stormwater model and other assumptions. The next step was determined to be that engineering staff would meet with the engineer Steve Maney to discuss the proposal in more detail. 8607 National This a carry over from a past meeting. The resident Alex would like to address the commission. The commission previously approved improvements consisting of an additional inlet at the low point. The inlet would provide a factor of safety with regard to inlet clogging and provides additional inlet capacity. The added inlet capacity would provide a benefit for lower intensity storms, for higher intensity storms the sewer is surcharged and the added inlet will not help. Alex requested that the inlet be placed further north near the fire hydrant and connect to the west side sewer. He was also concerned that there were fewer inlets on the east side of the street. He requested that something was done. The engineering department indicated that we stand ready to install the inlet at the low point. Old Business: The following topics were presented and discussed. Backyard Drainage Program Hey and Associates updated the program document per the comments received at the February 20th stormwater meeting. Significant revision included:  Added criteria for allowing sewer connection  Clarified Downspout redirection is not eligible but may be a perquisite  Flooding criteria changed from qualifying criteria to prioritization criteria General comments and questions were reviewed. It was discussed that the residents would not need to hire an engineer to apply for the program. Maintenance was discussed and whether the Village could hire a maintenance contractor. The projects with sewer work would be platted with a private sewer easement, which would document the maintenance responsibility and provide a means for forced maintenance when required. The commission discussed multiple lot projects. The Village engineer asked for feedback on whether multiple neighbors could contribute to a project and thereby be eligible for reimbursement. The discussion then shifted about whether a resident could be eligible for both the yard drainage program and flood control program, according to the program document residents would be eligible for both programs. It was agreed for the commissioners to provide comments by Friday. The commission voted to send the program to the Village Board for consideration pending receipt of final comments by Friday. Greenwood Stormwater Project Update Hey continues to work on the design and has met with the MWRD to review permit related issues. A design review subcommittee met to discuss finishes and surface improvements. An application to the DCEO Rebuild Illinois program was recently made. The plan is to go out to bid in early 2021. Niles Stormwater Ordinance Hey presented a memo that was reviewed with Community Development about the MWRD detention ordinance. Four scenarios were presented. Staff recommended incorporating the higher rainfall rates and using the MWRD methodology. The stormwater ordinance revision would be submitted to the commission at a later date. Stormwater Ordinance Update Hey and Associates provided staff with a mark-up for the ordinance revisions. The work plan is for staff to meet and review the edits prior to presenting them to the Commission. New Business: The following topics were presented and discussed. Detention Basin Monitoring Hey and Associates provided a verbal report on the basin monitoring project. Monitoring points were installed at the Holiday Inn Express, Panda Express, Oak Park Bioswale, and LoVerde Center Bioswale. The goal is to compare the underground vault detention operation to a traditional bioswale to make sure the systems are operating as intended. The Tech memo should be available before the next stormwater meeting. Public Comments Rosemary Palicki made public comments. She was unclear on what she was supposed to do to resolve her flooding. She was unsure if her only option was to apply for the program. She also had a question about the downspout ordinance. She requested a drainage pipe is installed in the rear yards all the way to Monroe. The chair asked about which options are available to Ms. Palicki and why downspouts are not being redirected. Community Development responded to downspout question and indicated that just directing downspouts to the rear is not a violation. If the downspouts are extended to the property line it is a violation, but if the downspout discharges at the base of the garage it is not a violation. Chair LoVerde felt downspouts could be redirected in many cases. Community Development indicated that in many cases the garage is below the street grade and that discharging towards the front would still end up in the low area in back. Community Development would look at this case to see if the neighbors down spouts could be redirected. The Village Engineer indicated Ms. Palicki would be eligible to connect to the combined sewer through the cost sharing program with the caveats previously indicated. Ms. Palicki inquired about the feasibility about a drainage pipe installed in the rear yards all the way to Monroe. The Village Manager indicated that past board were reluctant to spend money solving private yard flooding issues. However if the Board voted to fund a project outside of the cost sharing program that would be their decision. The Village Engineer indicated that installing a sewer through the rear yard is very tight corridor with garages, utility poles, fences, trees etc. The rear easement is only 10 feet wide. A directional bore likely could not get enough separation from the utility poles so open cut would be the only feasible construction methods. Open cut would mean removal of fences, gardens, landscaping resulting in major property impacts. The restoration costs would be significant. The Chair requested that Public Comments on Agenda Items first in the future. Next Meeting Date The date of the next meeting will be at the call of the chair. The meeting was adjourned at 10:13am