Category 4b (TMDL Alternative)
Communities do not have to wait for a formal TMDL planning process. You can take the initiative to voluntarily create programs to clean up impaired waters. Because these programs are locally controlled, there is an opportunity to reduce overall costs and you can exert greater control over the cleanup process.
Impaired waters with pollution control programs in place that are expected to solve pollution problems (i.e., meet water quality standards) are commonly referred to as “Category 4b” waters because they are moved from Category 5 (impaired and needs TMDL) of the State’s Integrated Report to Category 4b (impaired but TMDL not required). While pollution control programs are not TMDLs, they must have many of the same features, and there must be some legal or financial assurance that they will be implemented.
A Category 4b demonstration allows DWR and EPA to formally recognize actions that, from a local perspective, provide a more appropriate and effective response to impairment than TMDL development. DWR has developed guidance for communities interested in developing a plan to address impaired waters. The guidance describes the elements required to qualify for Category 4b. Communities interested in pursuing this option should review the guidance document and plan to meet with DWR’s Modeling and Assessment Branch prior to development. Some communities may find that they are already meeting most if not all of the required elements.
Example TMDL Alternatives
McDowell Creek, Catawba River Basin
Mecklenburg County completed a watershed plan for McDowell Creek in 2006. The plan is a ‘comprehensive roadmap for the management and restoration of surface waters in the entire watershed.’ Category 4b was a relatively new option at the time this plan was developed, however DWR recognized that all of the elements required for a 4b demonstration were included in the plan. DWR was able to successfully recategorize McDowell Creek to 4b in 2008.
Little Alamance Creek (under development), Cape Fear River Basin
In December 2010, the NC DWR requested public comment on the Draft Total Maximum Daily Load to Address Impaired Biological Integrity in the Little Alamance Creek Watershed, Alamance County, Cape Fear River Basin (Assessment Unit 16-19-11). The affected parties (Cities of Graham and Burlington and the NC DOT) requested the opportunity to address the impairment through development of an alternative TMDL plan that, when implemented, will allow for the achievement of the biological integrity standard in Little Alamance Creek.
Check back for progress updates as plan development and implementation proceeds.