The purpose of this article is threefold:
- To help people understand that the now approved acceleration of the Storm Water Master Plan will likely result in minimal relief to the 8th Ward;
- To highlight those issues which still need to be investigated and addressed by the City of Des Plaines; and
- To help people understand the process and timeline for completing the storm sewer upgrades
SANITARY SEWER INFILTRATION ISSUES
While the proposed storm sewer work will likely reduce the occurrences of street flooding, the real issue is the sanitary sewer system. This issue is more complex and potentially more troubling than the storm sewer issue.
Since August 2007, I have experienced seepage in my basement six(6) times due to a surcharge in the sanitary system. Four (4) of these instances occurred when there was NO street flooding. On February 26th, considering the possibility that my sewer line was blocked, I had it rodded. No significant blockage was found. I asked the City to investigate, which they immediately did. They stated that they jet rodded the system and televised it and no blockages were found. On March 7th, I experienced the same problem, indicating a surcharge in the sanitary system. The possible causes of this surcharge can include the following:
- Cross connections with the storm sewer system, possibly left over from the conversion of the combined sewer system
- Infiltration of ground water due to collapsed or broken pipes
- Infiltration due to tree roots into the system, causing larger breaches in the joints
- Infiltration through the pipe joints, which I believe are not sealed, (or the seals have deteriorated). It is my understanding that the sanitary pipes are 7 foot clay pipes with a bell and flange joint
- Infiltration through sanitary manholes that are below the water level of the flooded streets. This occurred in September and June
- Infiltration through yard cleanouts of individual houses. The typical cleanout cover has a square stud on it that allows a pipe wrench to loosen or tighten the cover. These are often broken off by lawn mowers, leaving a hole about 1 inch square. When the top of the cleanout is below the water level of the flooded area, the water pours in, filling the system.
At my September meeting with Mayor Moylan, Tim Oakley, and Jon Duddles, Oakley stated that the source of infiltration was ground water due to an old system. He assured me that there were no cross connections that the City was aware of. However, based on the level of the water in the system in non-storm situations, this is hard to believe.
In order to identify and address infiltration issues with the sanitary sewer system, the City should do the following:
- Perform a flow monitoring test on the entire system. They would measure the flow during periods of dry weather and compare it to the flow during various rain events.
- Perform an infiltration inflow analysis based on the results of the flow monitoring. The purpose of this is to limit the amount of water required to be treated. The hierarchy of the regulatory agencies that govern this is USEPA/IEPA/MWRD/Local Municipality. This is a result of the Clean Water Act of 1976. MWRD does not want to treat any more water than it has to.
- After the infiltration inflow analysis, the City should attempt to identify the major sources of infiltration. This could be done by televising the main lines. Blocked, broken, or collapsed lines or structures could be identified and repaired. Other solutions, short of replacing the entire system, would be to install liners in the worst lines. During times of street flooding the time it takes for the sanitary system to drain lags the storm system by 8-12 hours.
- Smoke tests could be conducted to determine if there are any cross connections.
The Metropolitan Water Reclamation District (MWRD) is the independent governmental authority that treats sanitary waste water. The plant that services our neighborhood is located at Elmhurst and Oakton. The sanitary lines in the 8th Ward were originally designed to flow north, where they were then routed east and south again to the treatment plant in Stickney. When the Oakton plant was built, an interceptor sewer was run from Golf Road (or thereabouts) south to the new plant. This was more practical than reversing the flow in all the neighborhoods. This interceptor collects all the sanitary lines running north and returns it to the plant for treatment. I assume the treated water is then released into Willow Creek.
In MWRD's
Manual of Procedures for the Administration of the Sewer Permit Ordinance, Section 6-5 specifically addresses the issues of groundwater infiltration and storm water inflow (I/I) into sanitary systems. This section addresses the reasons to minimize I/I, the limits of allowable I/I, the procedures local communities are required to perform to be in compliance, reporting requirements, and the long term maintenance and operations communities must undertake to remain in compliance. Based on my experience in the last year, it seems that the sanitary system may not comply with these requirements. It is unclear if the City is moving towards compliance or what MWRD's position on this is. There are potential sanctions for non-compliance, but the status of this whole situation is not known to me.
It is very unlikely that the proposed storm sewer improvements will have any impact on the sanitary system situation.
STORM SEWER ISSUES
It would be worthwhile to determine whether the design standard for the storm water system follows recommended guidelines set by expert authorities and those having jurisdiction. All new development above a certain area is required to detain some nominal quantity of storm water on site. This has been a requirement since the late 70s. MWRD sets the release rate and many cities, including Mt. Prospect, exceed that. I don't know about Des Plaines.
There is no enforceable "standard of care" that a municipality owes it's residents when it comes to storm drainage. There are health related issues that involve inadequate sanitary systems. These are overseen and enforced by the IEPA.
The design criteria should be re-examined. Duddles stated that the Plan was based on the October 2001 event. According to a Tim Oakley memorandum, that was approximately 3.4 inches in 4 hours. This is below the June 2009 event and significantly below the September 2008 event. The June event was over 5" between 3:00 a.m. and 10:00 a.m., and the September event was over 6.5 " between 3:30 a.m. and 9:30 a.m with another 1.5" by 5:00 p.m. (Being a gardener and contractor, I have kept a weather journal for over 10 years) It is not practical or economical to design to the September event, which probably falls into a 50-75 year occurrence. However, to change the design criteria, it may be necessary to commission another report or at least amend the current one.
SCHEDULING ISSUES
To elaborate on the time line
communicated by Jon Duddles
(Asst Dir. of Public Works and Engineering) posted
in a prior article:
- A formal Design Bid Package will have to be prepared by the city. This will tell the bidding engineering firms exactly what they will be bidding on. There will have to be some reasonable time allowed for the firms to put their bid together. If, during the bid process, questions or ambiguities are identified in the documents, addenda may be issued, and the bid period extended. The bid process could be 4 or even 6 weeks. After the bids are received, they will have to be reviewed for compliance with the requirements and budget. If the responsible low bid exceeds the budget, there will have to be some approval process to increase the design budget. If it's in budget, then the City will offer a contract. Budget increases and actual awards may require Council approval. Then the successful firm will enter into negotiations over the contract. This should be a relatively quick process. It is likely that the firm will have to post a bond, to ensure that the City is protected in the event breach of contract. Only when all this is done will the actual design start.
- There will likely be a preliminary design phase, in which numerous logistical issues are addressed, such as crossing Oakton St., getting easements, and coordinating with whatever utilities are currently running under Oakton. A point of discharge into Willow Creek will have to be determined. However, I'm told that approval to discharge into Willow Creek will not be required if it is in the City's limits. There will be issues with the elevations between the low point of the sewer on Marshall and the normal water level of the creek. There will be some minimal pitch required to ensure that the water will flow. I don't know how this will work after crossing Oakton. It seems likely that the sewer will be deep under Oakton to avoid whatever is currently there and may involve relocation, at least temporarily, of other utilities, i.e., Com-Ed, NICOR, etc. When this is done, the preliminary design may have to be submitted to various entities for review, i.e., MWRD, IDOT, etc. These entities will review and comment on the design, possibly making changes. The engineer will incorporate these changes into the design and continue. Upon completion of the design, it will likely have to be resubmitted to all entities for final approval. This process generally takes more time than it should, due to the bureaucracy involved.
- Then the Construction Bid process will start. It will be similar to the Design Bid process, but will not involve any intermediate steps. There will probably be a permit process and the City and contractor will have to agree on a schedule. There will be multiple trades involved, periodic inspections and approvals, and weather will be a factor. Material will have to be ordered, manufactured, and shipped. The construction process could easily extend to six months, probably no less than four at best. The work would probably start at the point of discharge and work backwards to keep the system from filling during rain events while work is proceeding. There may be an alternate to this. At some point, they will have to switch over from the old system to the new system. They would want all new asphalt and concrete work to be done by Thanksgiving, as well as any landscape restoration, although landscaping could be deferred until the following spring, if necessary.
In addition to the work already designated in the City's Storm Water Master Plan, there are other projects in the 8th Ward that are already completed or are in progress. These projects include the City's work on Jeffery Lane and their televising of the sewer lines, and Illinois American's work in the Waycinden area.
Jeffery Lane Issues
In August, Jon Duddles stated that the work on Jeffery was the replacement of the water mains. The structures that were installed were not catch basins, which imply storm sewer work, but rather valve vaults, which allow the city to isolate smaller sections of the water main. Thus, in the event of a water main break, they don't have to shut down the entire neighborhood to make repairs. This is standard engineering practice.
Televised Sewer Lines
In his response to my second letter,
Duddles listed the streets and dates that the sewer lines were televised.
- Dover, Danbury, Roxbury, Jeffery, and Devonshire 2009
- Jeffery, Doreen, and Westfield 2008
- Diamondhead Drive 2005
Illinois American
The Illinois American Water Association is a private utility company that services areas of Waycinden, dating back to before Waycinden was annexed. The conversion of the combined sewer system in Waycinden can only help our situation.
FLOOD CONTROL SOLUTIONS FOR HOMEOWNERS
I have reviewed the flood control systems on the City's website and have met with a contractor that installs these systems. Both the overhead sewer and flood control system should work if installed properly. In my opinion, the flood control system would be more effective. The overhead system may not work if storm water from drain tile is included. However, when the City states that the cost for the flood control system is around $8000, that does not include all the the electrical connections for the pump, landscape restoration, or repairs to interior finishes damaged by the installation. This system requires annual maintenance and has limitations on what can be run through the system; no Kleenex, tampons, Handiwipes, etc. The pump should be replaced every 6-8 years and it's expensive Neither of these systems work without power,
necessitating some form of back-up power. Typical battery back-up is only good for 4-8 hours, not sufficient to have helped in August of 2007. The City should be lobbied to increase their contribution to homeowners to 50% for installing this system. For residents who have these systems (or think they have them), I can only speculate that they are not performing as designed, or not designed properly, because they should work.
