Title
Tinley Creek Stabilization - September 2020 Update
History
In November of 2004, the Illinois State Legislature granted the Metropolitan Water Reclamation District (MWRD) of Greater Chicago the authority for general supervision of stormwater management in Cook County. The legislative act granting the authority required the preparation and adoption of a countywide stormwater management plan. In February of 2007, the MWRD's Board of Commissioners adopted the Cook County Stormwater Management Plan (CCSMP) by ordinance. The CCSMP was a high-level organizational plan and the first step in the development of the MWRD's countywide stormwater management program. Based on the CCSMP, the MWRD then studied each of the six watersheds in Cook County and developed Detailed Watershed Plans (DWP), which address regional stormwater problems in Cook County. The primary objectives of the DWPs were to document stormwater problem areas, evaluate existing watershed conditions using industry accepted hydrologic and hydraulic models, produce flow, stage, frequency, and duration information about flood events along regional waterways, and estimate damages associated with regional stormwater problems. The Cal-Sag DWP identified four potential projects within the Tinley Creek portion of the watershed. In 2010, feasibility/preliminary studies were prepared for each of the projects to determine the impact and benefits of the projects. Two of those projects are located in Orland Park and were selected for implementation based on the results of the preliminary analysis. Details for each project are provided below:
Project TICR-7 (Tinley Creek)
Description: Stabilize approximately 2,200 linear feet (LF) of Tinley Creek using a combination of retaining walls and bioengineering techniques. Estimated Construction Cost (2014 Dollars): $1,437,510
Project TICR-8 (Tinley Creek)
Description: Stabilize approximately 1,803 LF of Tinley Creek using a combination of retaining walls and bioengineering techniques. Estimated Construction Cost (2014): $2,303,411
In 2012, the Village met with the MWRD and their consultants to discuss the project scope including easements, utilities, timeframe, etc. At that time, construction was expected to take place in 2014 depending on the US Army Corps of Engineers permits and easement acquisition from the Orland Park property owners. The MWRD’s position regarding easement acquisition is that they will not purchase the easements or compensate the property owners with any additional financial or non-financial benefits other than those provided by the project itself. The Village offered assistance related to obtaining the easements from property owners, addressing any easement infringement issues, and any other outstanding items related to easements. As of 2013, the design of the proposed improvements was virtually complete (approximately 98%), but the project has not moved forward due to a lack of cooperation from property owners in obtaining the aforementioned easements.
The MWRD met with the Village on multiple occasions over the last several years to discuss the possibility of the Village taking over the project. The Village has expressed an interest in doing so; however, several concerns have been identified by the Village and are summarized below:
1. After the Village takes over the project, the maintenance costs of this project will be Village’s responsibility. How and who will pay for the maintenance costs?
2. The design was prepared in 2014 based on topographical information collected much earlier. Substantial changes in the existing conditions of Tinley Creek have occurred since then. Additionally, several areas that were not included in the original design limits have deteriorated and should be included in the project. Many of the previously designed areas will require redesign and substantially more improvement than anticipated in 2014.
3. The funding allocation prepared by MWRD in 2014 to construct the project would be substantially less than that required in 2020, or future years, and additional funds would be needed for areas that were not originally included or those that have deteriorated since the original design.
4. There were 31 easements initially identified for the project by MWRD and to date, only 9 property owners have agreed and signed the easement documents. Based on the current design, the outstanding 22 easements would need to be secured, as well as any new easements identified through the addition of other portions of the creek. Additional easements and/or agreements may need to be secured for utilities.
5. The United States Army Corps of Engineers permits previously issued for the projects that will need to be re-established, re-issued, or re-applied for.
Update from May 28, 2020 Meeting with MWRD
The Village’s engineering team and its consultant participated in a call with MWRD team on May 28, 2020. The following is a summary of this call:
- MWRD is willing to let the Village takeover the project and reimburse us for the design and construction costs.
- MWRD agreed that the Village’s consultant should re-evaluate the project and update the previous technical memorandum and cost estimates.
- MWRD is willing to expand the project limits and pay for it if the expansion meets their design criteria, although this is subject to identified projects costs and MWRD's ability to budget for those costs.
- It is possible there may be a need to expand the project limits but the expansion may not meet MWRD’s design criteria. In that case, the Village will make a decision if we pay for the expanded project limits. The intended advantage of this expansion would be to reduce future maintenance costs that would be Village’s responsibility.
The staff is recommending that the Committee authorize the staff to negotiate with MWRD the details and costs of this creek stabilization project.
Update from August 13, 2020 Meeting and Tinley Creek Field Visit with MWRD
The Village’s engineering team and its consultant revised the 2014 technical memorandum to evaluate the additional impact of six years on the creek erosion. Additionally, we evaluated if additional properties are impacted by the continued creek erosion. The evaluation shows additional erosion along the creek to the properties that were included in the 2014 design. Furthermore, 13 additional properties are impacted by the creek erosion. The planning level cost estimate for the updated project (total of 44 properties) is at $5.95 million.
The Village’s engineering team and its consultant met with MWRD representatives on August 13, 2020. The combined team also visited the major areas of concern along the creek. The following is a summary of this meeting and field visit:
- MWRD is still committed to the project. They updated their cost estimate from 2014 and the 2020 cost estimate is at $3.7 million. They may add minor sections to the project if they meet MWRD’s design requirements, and may pay for those additions as well. However, MWRD staff was hesitant to commit to the Village’s updated project cost of $5.95 million.
- MWRD stated, that the Village should consider paying for the additional properties or sections added to the project. At present, the estimated cost difference is $2.25 million. The Village staff believes the actual cost difference would be below $2 million after detail design and value engineering is completed.
- Staff needs direction about how to proceed with the $2 million cost difference between the total estimated project cost and MWRD’s funding.
- Staff also suggests establishing a Special Services Agreement (SSA) to pay for the maintenance of the improvements. Staff has estimated $25,000 to $50,000 will be needed annually to account for maintenance of the improvements covered under this project.
- The property owners still have to offer easements without compensation to complete this project under MWRD's parameters.
Financial Impact
There are no immediate financial impacts related to this request.
Recommended Action/Motion
No motion is needed at this time. This item is for discussion only.