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HomeMy WebLinkAboutVI. COW Agenda Item MWRD Storm Water Management Ordinance Mount Prospect Public Works Department INTEROFFICE MEMORANDUM TO: VILLAGE MANAGER MICHAEL E. JANONIS FROM: VILLAGE ENGINEER DATE: DECEMBER 3, 2009 SUBJECT: DRAFT COOK COUNTY WATERSHED MANAGEMENT ORDINANCE OVERVIEW Since 1970 the Metropolitan Reclamation District of Greater Chicago (MWRD) has regulated stormwater detention for developments within Cook County by establishing minimum stormwater detention regulations. While some communities still rely on the MWRD regulations, over the years many Cook County municipalities, including the Village of Mount Prospect, viewed the MWRD regulations as substandard and ineffective in preventing increased flooding levels from development within the county and have established and enforced their own preferred and more restrictive stormwater management regulations. Cook County communities recognized this disparity and acknowledged the need for enforcement of consistent regulations throughout the county. With the support of Cook County municipalities, the authority for general supervision of stormwater management in Cook County was conveyed to the MWRD pursuant to the passage of Public Act 93-1049 (Act) by the Illinois State Legislature on November 17, 2004. To that end, the MWRD has developed the Cook County Watershed Management Ordinance (CCWMO) and supporting Technical Guidance Manual (TGM) and has provided the municipalities a draft copy for review and comment. Many of the items contained within the CCWMO have been in place in the ordinances of the surrounding counties for years. The proposed CCWMO brings the stormwater management practices in Cook County up to the current and accepted stormwater management standards, insures that stormwater management practices will be standard across the entire county, and brings those standards up to the level of the surrounding counties. Briefly it should be discussed that Section 200.2.D on page 2-1 specifically exempts the City of Chicago from all requirements contained within the CCWMO. The City of Chicago Ordinance dated January 2009 is similar in many respects to the detention requirements contained in the CCWMO. In a recent Northwest Municipal Conference (NWMC) meeting to review the CCWMO, it was stated that after implementation by the MWRD, the City of Chicago will review the ordinance and decide if it is appropriate to adopt. During the review of this draft of the CCWMO, staff has attended numerous meetings sponsored by MWRD and the Northwest Municipal Conference (NWMC) to gain a better understanding of the impacts of the ordinance and to hear other communities' comments. While staff is supportive of consistency in regulations, staff has concerns about this draft of the ordinance as it relates to our current Village Ordinance, the Impacts to Development within the Village and the Impacts to the Village. Page 1 of 8 Cook County Watershed Management Ordinance 2nd Review December 3, 2009 ORDINANCE COMPARISON The CCWMO establishes regulations for all aspects of stormwater management, including water quality treatment, wetland and riparian area protection, and floodplain regulations, in addition to stormwater detention. The impacts to the Village in each of these areas are discussed below: Stormwater Detention (VoMP Code Section 16.603/ CCWMO Sections 504 and 506) Please note that the Village Code can be viewed on line (Chapters 15, 16 and 22), and the complete CCWMO can be viewed at: http://www . mwrd. org/i rj/portal/anonym ous/WM 0 Pu blicReview Staff Comment: The proposed CCWMO will not cause stormwater detention to be required for more developments than currently required by the Village Code. Furthermore, Staff does not anticipate that the proposed CCWMO would cause a significant increase in the amount of stormwater detention to be required beyond that required by current Village Code for most sites. However, the proposed CCWMO will require the Village to adopt new methods and acquire new software and training to calculate the required stormwater detention. Discussion: Current MWRD ordinances require stormwater detention to be provided for single- family residential developments larger than 10 acres, and all other developments larger than 5 acres. The proposed CCWMO reduces these thresholds to 5 acres and 3 acres respectively. These requirements are not as strict as the current Village requirements; the Village requires stormwater detention for all developments larger than one acre. Furthermore, for developments smaller than 1 acre, the Village requires a fee in lieu of stormwater detention. The dramatic changes proposed in the CCWMO are in the means by which stormwater detention is calculated. Both the Village and MWRD currently calculate stormwater detention storage using the "Modified Rational Method". This is a simple spreadsheet method used to determine the total volume required. It is not very adaptable for complex watersheds, and is not accurate for large tributary areas. The CCWMO requires that a "hydrograph" method be used. These hydrographs are used in computer modeling of the watersheds, and so are much more able to accommodate large, complex watersheds, but are not necessarily any more accurate for small watersheds. While Staff is familiar with several hydrograph computer modeling methods, the Village currently does not possess any hydrograph computer modeling software. A summary of some of the more significant changes proposed by the CCWMO is included with this report. It should be noted that, while the methods for computing stormwater detention vary greatly, the proposed CCWMO nearly doubles the amount of stormwater detention that would be required under current MWRD ordinances, but does not necessarily require more storage than current Village Codes. Staff has reviewed the example provided in the TGM, and calculated the stormwater detention that would be required under the current Village Code: Example Site from Technical Guidance Manual: 3 acres, 75% lot coverage Proposed CCWMO: Current VoMP Code: Max. Release Rate 0.45 cfs 0.60 cfs Required Storaqe Volume 0.9 ac-ft 0.96 aC-ft Page 2 of 8 Cook County Watershed Management Ordinance 2nd Review December 3, 2009 Water QualitvNolume Control (No specific VoMP regulations / CCWMO Sections 503 and 505) Staff Comment: For sites even as small as 0.5 acres, the developer will be required to provide "water quality control" or "volume control". The time to design and review the water/quality control facilities, and the cost to install these facilities are delays and costs not currently undertaken by the developer. Discussion: While the proposed CCWMO does not require stormwater detention for small sites, it does include requirements for stormwater quality and volume control. For all single-family residential developments larger than 1 acre, and all other developments larger than 0.5 acre some water quality or volume control measures will be required. Although several options are discussed in the TGM, the preferred method as listed in the CCWMO is to provide retainage for the first 1" of stormwater runoff from all impervious surfaces. This volume may be retained either above or below ground. It must be stressed that this is retention of stormwater - no outlet for the water is provided; all water must infiltrate or evaporate. The design requirements for such retention areas include the determination of the seasonally high water table to insure that the bottom of the retention area is at least 3' higher than the water table. Meeting the technical requirements of the water quality or volume control regulations will require the expenditure of additional time and money by the developer. Erosion & Sediment Control (VoMP Code Section 16.703/ CCWMO Section 400) Staff Comment: No significant additional erosion or sediment control measures would be imposed by the CCWMO. Discussion: The proposed CCWMO includes requirements for erosion and sediment control largely contained in the National Pollution Discharge Elimination System (NPDES) requirements already required by the Illinois Environmental Protection Agency. The Village already enforces the NPDES requirements, so no significant additional erosion or sediment control measures would be imposed by the CCWMO. Floodplain Re~ulations (VoMP Code Chapter 22 / CCWMO Sections 601 and 602) Staff Comment: The proposed CCWMO includes floodplain regulations largely contained in the National Flood Insurance Program (NFIP) requirements. Chapter 22 of the Village Code already meets or exceeds the regulations included in the NFIP requirements, so Staff anticipates that few significant additional floodplain restrictions would be imposed by the CCWMO. Discussion: While the restrictions pertaining to construction within the floodplain do not vary significantly between the Village Code and the CCWMO, the CCWMO includes a potential change regarding where the floodplain restrictions are to be applied. The "Flood Protection Elevation" (FPE) is defined as "the highest 100-year flood elevation as determined in Section 601.9 plus one foot of freeboard". Section 601.9 refers to the Flood Insurance Studies performed by the Federal Emergency Management Agency (FEMA) and currently adopted by the Village, and adds "1 OO-year inundation elevations identified in the District's DWP's" (Detailed Watershed Plans). Example 7.5 Page 3 of 8 Cook County Watershed Management Ordinance 2nd Review December 3, 2009 on page 6-16 of the TGM details a case in which the inundation levels noted in the DWP are higher than the Base Flood Elevation (BFE) determined by FEMA, so the inundation levels are used in calculating the FPE. The Detailed Watershed Plans are not yet available; in a public hearing held on November 18th it was noted that the DWPs will not be available until Fall of 2010. Because the DWPs are not yet available, Staff cannot yet determine the impact of the inundation levels on construction within the floodplain areas throughout the Village. Both the floodplain limits established by FEMA any the Inundation levels defined by the MWRD both attempt to describe the area that would be flooded during the 1 OO-year storm. It would be awkward and cumbersome to have two differing sources for what should be the same information. The MWRD should submit the Inundation Levels to FEMA for review and have the floodplain maps changed if appropriate. (It should be noted that because the inundation levels contained in the MWRD's DWP are not associated or approved by FEMA, insurance requirements, participation in the NFIP, and the Village's Community Rating System (CRS) rating will be unaffected.) Wetland Area Protection (No specific VoMP regulations / CCWMO Sections 603-605) Staff Comment: Section 604.18 on page 6-17 prohibits any development within a wetland buffer area that would "adversely impact the quantity, quality, or temporal and areal distribution of flows entering and adjacent wetlands or waters". For all projects requiring a Watershed Management Permit, the developer will have to obtain a statement by a "Qualified Person" confirming or denying the presence of wetlands on and within 100' of the property. (Section 302.5 on page 3-3) If a wetland is identified, the associated "wetland buffer area" will have to be delineated. Significant restrictions apply to any construction within the wetland and wetland buffer areas. Discussion: The Village Code does not contain any specific wetland regulations; all jurisdictional wetlands are currently under the jurisdiction of the U.S. Army Corps of Engineers (USCOE). The CCWMO ordinance duplicates many of the requirements contained in the "404 Permit" issued by the USCOE, and adds the following additional restrictions for "Wetland Buffer Areas". Wetland buffer areas are defined as "areas adjacent to wetlands to be left open for the purposes of eliminating or minimizing adverse impacts" to the wetland. These buffers will likely be 30' wide, but may be as wide as 50' or 100' depending upon the characteristics of the wetland. So while the construction restrictions applied to the wetland areas will not significantly change, the proposed CCWO will add the additional restrictions attached to the wetland buffer areas. Riparian Environment Protection (No specific VoMP regulations / CCWMO Section 607) Staff Comment: Section 607.3.C on page 6-21 prohibits any development within a riparian environment that would "change" the quantity, quality, or distribution of flows entering and adjacent wetlands or waters. For all projects requiring a Watershed Management Permit, the developer will have to obtain a statement by a "Qualified Person" confirming or denying the presence of riparian environment on and within 100' of the property. (Section 302.5 on page 3-3) Significant restrictions apply to any construction within the wetland and wetland buffer areas. Page 4 of 8 Cook County Watershed Management Ordinance 2nd Review December 3, 2009 Discussion: Riparian environments are defined as those areas "between aquatic and upland ecosystems adjacent to a waterway or body of water". Similar to the wetland buffer areas, the riparian environment will likely be designated as 30' wide, but may be as wide as 50' or 100' depending upon the characteristics of the waterway. While the definition would appear to include the backyards of all properties along the creeks through the Village, page 6-71 of the TGM contains the exceptions that impervious surfaces and turf grass are not to be considered as riparian environments protected by the CCWMO. Coordination with Forest Preserve District (No specific VoMP regulations / CCWMO Section) Staff Comment: Section 300.6 on page 3-1 states that an applicant "proposing (a) point discharge at a location adjacent to holdings or property of Forest Preserve District of Cook County (FPD) should contact the FPD and review the FPD's stormwater management policy." This coordination with the FPD is not currently required, and could add another tier of submittal and review, causing further delays to developers. Discussion: The CCWMO states that the applicant "should' coordinate with the FPD. The requirements of this section should be clarified. Are applicants encouraged or required to submit plans to the FPD? What jurisdiction does the FPD have? What constitutes "adjacent"? Is the FPD subject to this ordinance? How are FPD policies different from this ordinance? IMPACT TO DEVELOPERS The vast majority of permits issued by the Village of Mount Prospect are for work on single family residences (tear downs & rebuilds, additions, garages, etc.) that disturb less than 0.5 acre. The proposed CCWMO will have minimal impact on these types of projects. However, the CCWMO will impact most residential subdivisions and commercial, industrial, and multi-family projects. The greatest impacts to the developers of these types of projects will not be through increased stormwater detention or floodplain regulations; the Village's current regulations are similar in impact to those proposed in the CCWMO. The greatest impact to developers will be in the additional time and expense incurred to obtain the Watershed Management Permit from the MWRD, and from the additional restrictions placed on developing near wetland areas or riparian environments. To illustrate the impact the proposed CCWMO will have on development, we have outlined the additional steps that developers will have to take to meet the CCWMO permitting requirements. (New items are shown bold; items that are required under the current Village Code but are significantly altered by the proposed CCWMO are shown normal type.) 1. A statement by a "Qualified Person" confirming or denying the presence of floodplain, wetlands, and/or riparian environments on and within 100' of the property. (Section 302.5) 2. Stormwater Management Submittal conforming to Article 5. A. Compute the site stormwater runoff characteristics must be modeled using a hydrograph method. (Section 502) B. The first 1" of stormwater runoff from impervious surfaces must be retained. (Section 503) Page 5 of 8 Cook County Watershed Management Ordinance 2nd Review December 3, 2009 C. Although stormwater detention is currently required for projects larger that 3 acres (5 acres if single-family residential), the means for calculating the required storage are more complicated and time consuming. (Section 504) 5. Floodplain Submittal conforming to Section 602. Based upon the Inundations Areas eventually included in the DWP, the areas subject to floodplain restrictions may increase dramatically. 6. Wetland Submittal conforming to Sections 603 - 605. A. The proposed CCWMO requires the applicant to determine the presence, limits, classification and jurisdiction of the wetlands not only on site, but also within 100' of the site. B. Determine the limits of the wetland buffer area. (Section 603.8) C. Determine impact to wetland and buffer area, and appropriate methods of mitigation. (Section 604) D. Annual reports monitoring the constructed mitigation measures will have to be submitted to the MWRD for 5 years following construction, or "until such time that the performance criteria has been met". (Section 604.17) 7. Riparian Environment Submittal conforming to Sections 606 - 607. A. Determine the limits, classification and jurisdiction of the riparian environment. (Section 606) B. Determine the impact to the riparian environment and appropriate methods of mitigation. (Section 604) C. Annual reports monitoring the constructed mitigation measures will have to be submitted to the MWRD for 5 years following construction, or "until such time that the performance criteria has been met". (Section 607.11) IMPACT TO VILLAGE It is not clear what the municipalities' role will be in administering Watershed Management Permits for the proposed CCWMO. However, it is clear that at a minimum, additional Staff time will be required to assist the applicants in preparing the submittals and reviewing the designs to meet the additional requirements and restrictions contained in the CCWMO. Furthermore, hydrograph modeling software (and the associated training) will have to be obtained. The definition of the "Co-Applicant" included in Appendix A on page 3 identifies the Co-Applicant as "any municipality ... required to jointly sign a Watershed Management Permit. The NWMC has made the statement in a draft letter to the MWRD stating that the role and responsibilities of the Co-Applicant must be clearly defined. Staff strongly agrees with the NWMC in needing to have the Co-Applicant's role defined. The only mention of these responsibilities is in Section 700.4, where the CCWMO states that "maintenance is the responsibility of the applicant and co-applicant of the development. . . . however, ultimate responsibility for maintenance of stormwater management facilities, including the site runoff storage facilities, lies with the co-applicant." Consequently, under the proposed CCWMO, the Village may be held responsible for the maintenance of private stormwater management facilities not currently maintained by the Village. Section 301.1 on page 3-2 also includes triggers that would require the Village to obtain a Watershed Management Permit for several types of municipal projects, increasing the cost and time involved. These projects include, but are not limited to those listed below: Page 6 of 8 Cook County Watershed Management Ordinance 2nd Review December 3, 2009 Section 301.1.C: A permit is required for all projects that disturb more than 0.5 acres. This is intended to include such municipal projects as pavement installation/widening. (Village Streetscape, the Kensington Road widening, the New Sidewalk Program, and detention pond maintenance require a Watershed Management Permit.) Section 301.1.C.(3): A permit is required for "excavation within the rights-of-way or public utility easements ... for the purpose of installing or maintaining utilities" unless the area disturbed is less than 0.5 acres, and the area is restored with vegetative cover. (The Prospect Meadows watermain installation and similar projects would require a Watershed Management Permit.) Section 301.1.D: A permit is required for projects that propose "sewers, drainage, or detention in combined sewers" unless the area disturbed is less than 0.5 acres. (The Backyard Drainage Program and similar projects may require a Watershed Management Permit.) RECOMMENDA liONS The proposed CCWMO includes many aspects of the accepted current standards for stormwater management. These standards have been in place in the surrounding counties for many years. The proposed CCWMO brings Cook County's stormwater management practices in line with these surrounding counties, and so Staff supports the concepts contained within the CCWMO. However, several questions and concerns must be addressed prior to the MWRD adoption CCWMO, and before Staff can recommend approval of the CCWMO to the Village. 1. The NWMC has made the statement in a draft letter to the MWRD stating that the MWRD should have an economic impact study performed, and provide the fee schedule and anticipated review time associated with Watershed Management Permits. Staff strongly agrees with the NWMC in that this information is important in assessing the impact that the proposed CCWMO will have on development within the Village. 2. The duties and responsibilities of both the Applicant and Co-Applicant must be clearly and completely defined. This should include but is not limited to permitting, review, inspection, and long- term maintenance responsibilities. 3. We strongly suggest that the MWRD delete the floodplain regulations sections from the CCWMO, and leave review and permitting of projects in floodplain areas with the Village. As a requirement of the National Flood Insurance Program (NFIP), the Village has adopted certain floodplain regulations into the Village Code. (See Chapter 22 of the Village Code.) The proposed CCWMO does not supersede the Village's responsibilities to remain in the NFIP. Furthermore, the Village is periodically audited by FEMA to insure the Village's compliance with the NFIP. This redundant review of projects within the floodplain - Village and the MWRD - is unnecessary. 4. We strongly suggest that the MWRD delete the wetland regulations sections CCWMO, and leave review and permitting of projects near wetland areas with the USCOE. Under Section 404 of The Clean Water Act, the U.S. Army Corps of Engineers has jurisdiction and permit authority over all "jurisdictional" wetlands. The proposed CCWMO does not supersede the USCOE's authority, or negate the responsibility for the applicant to obtain a 404 permit from the USCOE. This redundant review - USCOE and the MWRD - is unnecessary. Page 7 of 8 Cook County Watershed Management Ordinance 2nd Review December 3, 2009 5. As mentioned previously, the CCWMO proposes floodplain regulations be based on the Flood Protection Elevation, which in turn will be based on either FEMA's base flood elevation, or the MWRD's Inundation Levels. Because these Inundation Levels are referred to in the CCWMO, the CCWMO cannot be completed until these levels are established. SCHEDULE As mentioned previously, the MWRD has given the municipalities the opportunity to review and comment on the draft CCWMO. Staff will provide these comments and concerns, along with a list of questions regarding the more technical details of the CCWMO to the MWRD prior to the deadline of December 31, 2009. After all comments are resolved, and the CCWMO is revised as appropriate, the MWRD will present the final CCWMO to their Board of Commissioners and request approval. It is anticipated that the CCWMO will become effective 180 days after adoption by the MWRD Board of Commissioners. By the date that the CCWMO becomes effective, the Village Code will have to be modified to refer to the CCWMO, and eliminate any conflicts with the CCWMO. In a recent meeting, the MWRD stated that they hope the process is completed and the CCWMO becomes effective toward the end of the first quarter of 2010. Please feel free to contact me if you have any questions. ~~~ C: Director of Public Works Glen Andler Director or Community Development William Cooney Deputy Director of Public Works Sean Dorsey Project Engineer Chuck Lindelof C:\Documents and Settings\djarosz\Local Settings\Temporary Internet Files\OLKE2\CCWMO Report - Memo to Board.doc Page 8 of 8 List of Acronyms BFE CCWMO CRS DWP FEMA FPD FPE MWRD NFIP NPDES NWMC TGM USCOE VOMP Base Flood Elevation Cook County Watershed Management Ordinance Community Rating System Detailed Watershed Plan Federal Emergency Management Agency Forest Preserve District Flood Protection Elevation Metropolitan Water Reclamation District of Greater Chicago National Flood Insurance Program National Pollution Discharge Elimination System Northwest Municipal Conference Technical Guidance Manual U.S. Army Corps of Engineers Village of Mount Prospect