160 likes | 175 Vues
Explore how cities in Carson, Compton, Gardena, Lawndale, Irwindale, South El Monte, and West Covina are implementing their Integrated Watershed Management Plans. Learn about compliance options, challenges, and enhancements for achieving water quality standards. Collaboration with NGOs and the iterative process are key factors in these initiatives.
E N D
IWMP Summary Presentation Carson, Compton, Gardena, Irwindale, Lawndale, South El Monte, and West Covina
IWMP Summary • I-WMPs prepared for Carson, Compton, Gardena, Lawndale, Irwindale, South El Monte, and West Covina • The MS4 permit provides 3 compliance options (SWMP, WMP, and EWMP) • Cities chose the WMP because it was the least stringent • Cites preferred the SWMP but RB staff is of the opinion that the SWMP is not a valid option – despite the fact that the MS4 Permit clearly identifies the SWMP as not only a valid compliance option but the only valid compliance option (more on this latter) • I-WMP/WMP carry the disadvantage of providing limited compliance with TMDLs – interim only – and through a “safe harbor” that forgives violations while the I-WMP/WMP are being implemented • Enviro NGOs contend that the safe harbors are illegal (we agree – only the iterative process mandated by WQO 99-05 provides protection during program development implementation by preemptinginstead of forgiving violations through the implementation of a SWMP or WMPs
IWMP Summary • I-WMPs SQMPs that have been revised to reflect changes to each of the 6 core programs (e.g., LID for the development planning program and Green Streets for the Public Agency Program) • I-WMP also reflects sub-watershed considerations such as TMDLs (real v. pseudo TMDLs) • Example: Reach 2 of the Rio Hondo is not subject to the metals or trash TMDL because none of these pollutants is on the 303(d) list • Cities are not subject to hydromodification because they all drain to flood control channels that have hardened walls that prevent stream bank erosion
IWMP Summary • I-WMPs propose enhancements (BMPs) that will be based on outfall monitoring against ambient standards through a true iterative process • Type and extent of BMPs needed to meet TMDL waste load allocations and other numeric water quality standards will be determined through computer modeling (e.g., adding more project categories to the LID list, requiring existing industrial and commercial building to route roof-top to areas of infiltration, improving parks and vacant properties within cities to function as runoff collection areas) • The iterative process is meant to achieve water quality standards over a period time – as noted in the draft North Orange County MS4 Permit: Iterative Process. This Order is based on an iterative approach that, in summary, is comprised of planning, implementing, evaluating, and improving BMPs carried out as part of the Co- Permittees’ storm water programs. Multiple iterations will occur during this permit term, and are likely to occur over multiple permit terms, to achieve water quality objectives.
IWMP Summary Basic Iterative Process Problem Resolution Cycle
IWMP Summary • Computer Modeling • Type and extent of BMPs needed to meet TMDL waste load allocations and other numeric water quality standards will be determined through computer modeling (e.g., adding more project categories to the LID list, requiring existing industrial and commercial building to route roof-top to areas of infiltration, improving parks and vacant properties within cities to function as runoff collection areas) • Computer modeling has resulted in demonstrating that the cities are meeting TMDL waste load allocations between 70 and 77% • Based on assumed values assigned to stormwater management program that will reduce pollutants to attain TMDL waste load allocations • Future modeling based on outfall monitoring results (instead of in-stream monitoring) measured against ambient standards should a more accurate TMDL compliance picture for each of the cities • In fact, it would have been advisable to defer RAA/computer modeling after each of the cities MS4s have been characterized based on outfall monitoring data
IWMP Summary • NGO Concerns Regarding Submittals • Did not submit RAA documents • False: these were submitted along with computer modeling data • Maps showing outfall monitoring locations are missing • False: Maps were in fact submitted • Did not comply with hydromodification requirement • False: None of the cities should be subject to hydromodification because they all discharge to conveyances that are hardened • NGOs point to earthen bottom channels: they have nothing to do with hydromodification because each of the channels are hardened and, therefore, are not vulnerable to stream bank erosion
IWMP Summary Compton Creek Example Of Hardened Walls/Soft Bottom
IWMP Summary • NGO Concerns Regarding Submittals • WMP Submittals Read Like Legal Comment Letters • Perhaps – Cities reiterated the legal arguments raised in their administrative petitions challenging the WMP. Legal arguments were raised so that the cities WMP submittals, which are voluntary, would not be construed to mean that the cities are okay with the WMP as a compliance option • Cities Legal arguments include: • The iterative process exists even through WQO 99-05 (supported by USEPA) – despite the Regional Board’s opinion to the contrary • Cities are not legally required to conduct in-stream monitoring; only monitoring at the outfall (end of the regulatory line for MS4 permits) • Cities are not required to meet TMDLs in non-stormwater discharges (from outfalls) – the reason: no iterative process applies to non-stormwater (per WQO 2009-0008) • Cities are required to comply with ambient (dry weather standards) not wet weather ones (per 2001-15) • Cities are only required to comply with legitimate TMDLs that are 303(d) listed • WQBELs cannot be the same as TMDL WLAs (they translate WLAs in compliance actions such as BMPs and surrogate parameters) – this will aid in voiding the WMP and EWMP which should be covered by WQBELs but are not
IWMP Summary • NGO Concerns Regarding Submittals • NGOs recommend that WMP submittal be rejected -- doubtful because: • State Board indicated that a tentative order will be issued by mid-November addressing the cities legal arguments – we believe it will uphold the iterative process to be applied to the SWMP and WMP • Were the Regional Board to reject the WMP, staff has opined that the cities would be subject to SWMP/Minimum Control Measures which require absolute compliance with TMDL WLAs • The Permit, however, under V.A.1-4 makes clear that SWMP implementation in a timely and complete manner, together with permittee’s appropriate response to reporting and responding to exceedances prevents Receiving Water Limitation violations – no such provision exists for the WMP or EWMP • Note: the V.A.1-4 does not include the WMP or EWMP as being subject to the iterative process (WMP/EWMP are covered under safe harbors that foregive violations – on this we agree with the NGOs: there is no such thing as a safe harbor that forgives violations
IWMP Summary • NGO Concerns Regarding Submittals • NGOs recommend that WMP submittal be rejected -- doubtful because: • State Board indicated that a tentative order will be issued by mid-November addressing the cities legal arguments – we believe it will uphold the iterative process to be applied to the SWMP and WMP • Were the Regional Board to reject the WMP, staff has opined that the cities would be subject to SWMP/Minimum Control Measures which require absolute compliance with TMDL WLAs • The Permit, however, under V.A.1-4 makes clear that SWMP implementation in a timely and complete manner, together with permittee’s appropriate response to reporting and responding to exceedances prevents Receiving Water Limitation violations – no such provision exists for the WMP or EWMP • Note: the V.A.1-4 does not include the WMP or EWMP as being subject to the iterative process (WMP/EWMP are covered under safe harbors that foregive violations – on this we agree with the NGOs: there is no such thing as a safe harbor that forgives violations
IWMP Summary • Executive Officer recently denied submittals for my cities. • Means that compliance defaults to the stormwater management program • RB staff have concluded that this option requires absolute compliance with TMDLs • Permit clearly says that compliance is determined by implementing the SWMP which is subject to the iterative process • Staff disagrees but without compelling reasons
IWMP Summary • A. Receiving Water Limitations • 1. Discharges from the MS4 that cause or contribute to the violation of receiving water • limitations are prohibited. • 2. Discharges from the MS4 of storm water, or non-storm water, for which a Permittee • is responsible20, shall not cause or contribute to a condition of nuisance. • 3. The Permittees shall comply with Parts V.A.1 and V.A.2 through timely • implementation of control measures and other actions to reduce pollutants in the • discharges in accordance with the storm water management program and its • components and other requirements of this Order including any modifications. The • storm water management program and its components shall be designed to achieve • compliance with receiving water limitations. If exceedances of receiving water • limitations persist, notwithstanding implementation of the storm water management • program and its components and other requirements of this Order, the Permittee • shall assure compliance with discharge prohibitions and receiving water limitations • by complying with the following procedure:
IWMP Summary • While staff disagrees that this provision does not apply to the Stormwater Management Program, it has not explained what purpose it serves; what does the iterative process apply to? • This issue will be resolved through the State Board’s order which will be issued in a few weeks
IWMP Summary Questions?