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Nonpoint Source Water Pollution

Nonpoint Source > Progress Evaluation > When to Update a Watershed Management Plan When to Update a Watershed Management Plan

A watershed management plan (WMP) is a living document that will require periodic updates as landuse and water quality change over time and best management practices (BMPs) are implemented. During the WMP development process the watershed group determined how often the WMP will be reevaluated; typically every 5 years (or annually to more closely track progress). As part of the evaluation process, the group should review the implementation activities in the work plan or action register, the monitoring results, and any other chosen indicators to determine the effectiveness of the implementation efforts and whether progress is being made toward achieving the WMP goals. If implementation efforts are on track and interim milestones are being met, celebrate success and carry on! If it is determined that interim milestones or pollutant reduction goals are not being met, consider the following questions and make any necessary adjustments before modifying the WMP:

  • Did weather-related causes postpone or affect implementation?
  • Was there a shortage of technical assistance?
  • Did you misjudge the amount of time needed to install some of the practices?
  • Did you fail to account for socio-economic or other barriers to adoption?
  • Are you choosing, implementing and using the management measures correctly (i.e., are they being installed, operated, and maintained correctly)?
  • Do you need to wait longer before you can reasonably expect to see results?

A WMP may or will need to be updated for various reasons including:

  • Documented significant landuse or water quality changes in the watershed.
  • Water quality impairments still persist after the WMP has been implemented to a level that the problems originating in the critical areas have been remediated and new critical areas need to be selected.
  • The WMP evaluation showed pollutant reduction goals are not being met, and the questions above and other relevant questions or issues the group may identify have been considered.

When it is determined that a WMP needs to be updated, the group will need to establish whether this entails rewriting the WMP or simply revising the WMP. The term (and ultimately the process) chosen depends on what needs to be done. Before updating a WMP, the watershed group should discuss the revision with their IDEM Watershed Specialist. IDEM and the watershed group will decide which checklist elements need to be revised and make a determination on whether the WMP needs to be rewritten or just requires a few revisions. An updated WMP must be approved by IDEM before Section 319 funds can be awarded for implementation. Section 319 or 205j grant funds may be available to help groups update their plan (see the Section 319 and 205j Grant Funding section below for more information).

Rewriting a Watershed Management Plan

Rewriting a watershed plan implies that most of the WMP needs to be updated, incorporating the entire planning process. The WMP will be required to meet the IDEM 2009 WMP Checklist.

A rewrite is required if all of the following WMP checklist requirements are determined to be outdated enough to impede successful implementation of the WMP:

  1. Baseline information on land use and land characteristics;
  2. Baseline information on current water quality;
  3. Nonpoint source pollution sources;
  4. Critical and/or priority areas;
  5. Goals; and,
  6. BMPs or measures needed to achieve goals.

Projects rewriting a watershed management plan must devote a sufficient amount of time to the process to gather essential data, make decisions, and educate and engage watershed stakeholders. IDEM encourages projects rewriting a WMP to have at least 6 steering committee meetings during the rewriting process. Implementation may not occur in the watershed until the rewritten plan is approved.

Revising a Watershed Management Plan

Revising a watershed plan implies that only select WMP checklist requirements need to be updated. The WMP updates must meet the checklist requirements for the particular (2003 or 2009) checklist the WMP was originally approved under. WMPs approved under the 2001 checklist must be rewritten to meet the 2009 WMP Checklist to be eligible for implementation funding. Since there needs to be a clearly understandable and logical train of thought throughout the WMP, when one section of the WMP needs to be revised, other sections may also need some revision. Below are the elements of a WMP that commonly need to be revised, along with related elements that will need to be considered. The relevant 2003 WMP Checklist and 2009 WMP Checklist element numbers are shown in parentheses respectively.

If you want to revise:

  • Stakeholder Concerns: check every subsequent checklist requirement through Measurable Milestones (Elements 4-19 or Elements 3-28)
  • Baseline Conditions: check every subsequent checklist requirement through Measurable Milestones (Elements 5-19 or Elements 7, 11-28)
  • Causes: check every subsequent checklist requirement through Measurable Milestones (Elements 7-19 or Elements 18-28)
  • Specific Sources: check every subsequent checklist requirement through Measurable Milestones (Elements 8-19 or Elements 19-28)
  • Problems in the Watershed: check the baseline conditions and every subsequent checklist requirement through Measureable Milestones (Bullet 5-19 or Elements 7, 11-28)
  • Estimated Existing Loads: check Baseline Conditions through Monitoring Plan (Elements 5-20 or Elements 7, 11-32)
  • Critical Areas: check Baseline Conditions through Measureable Milestones (Elements 5-19 or Elements 7, 11-28)
  • Water Quality Improvement or Protection Goals: check Baseline Conditions through Monitoring Plan (Elements 5-20 or Elements 7, 11-32)
  • Indicators: check the Indicators and Monitoring Plan (Elements 12, 13, 20 or Elements 23, 32)
  • BMPs or Measures needed to achieve the Goals: check Goals & Indicators and through Measurable Milestones (Elements 11-19 or Elements 22-28)

Other considerations when revising a watershed management plan:

  • Additional areas may be added to an existing WMP if the delineation of the HUC(s) was changed by USGS when they converted from an 11 or 14-digit HUC to a 10 or 12-digit HUC and the WMP no longer matches the newly defined watershed boundaries. Additional areas may also be added if the applicant wants to expand the coverage of the WMP by adding an adjacent watershed. Implementation may occur with Section 319 funds only in the current approved WMP critical areas until the revised WMP is approved.
  • If a NPS TMDL is developed after the WMP is finished, the plan will need to be revised to be consistent with the load allocations in the NPS TMDL.

Section 319 and 205j Grant Funding

In order for a group to receive Section 319 or 205j funding for WMP updates, at least two of the WMP sections below must be outdated:

  • Information on land use and land characteristics
  • Current water quality
  • Pollution sources
  • Critical areas
  • Goals
  • Objectives designed to achieve the goals

Judging what is “outdated” is subjective, and groups should make this determination using their best professional judgment and discussing with IDEM. The result will determine whether the process for rewriting or revising the WMP is applicable. WMPs approved by IDEM within the last five years are not eligible to receive funding for revision, unless extraordinary circumstances necessitate it and it is pre-approved by IDEM. For more information on whether your WMP revision qualifies for funding, read the specific requirements in the IDEM 319/205(j) Grant Application Instructions.

Additional Guidance