Wet Weather Operating Plans and Their Strategic Use

1
Wet Weather Operating Plans and Their Strategic
Use

• Paul Calamita
• AquaLaw
• Presentation to
• NACWA Wet Weather Partnership Workshop
• Chicago, IL
• June 1, 2006

2
Overview

• Wet weather operations plans (WWOPS)
• Why CSO communities develop them
• Approach to Development
• Strategic Use
• Conclusion

3

• Why CSO Communities Develop WWOPS

4
Why CSO Communities Develop WWOPs

• Some expressly required by State permitting
  agencies
• NYSDEC requires formal plans
• Secondary 1.5 times dry weather flow
• Primary 2 times dry weather flow
• Other states require informal plans/descriptions

5
Why CSO Communities Develop WWOPs

• Others prepared to fulfill
• NMC requirement
• Maximize flow to the treatment plant
• Maximize flow treated at the plant
• Proper OM
• Blending/Bypass Permit requirements
• Secondary treatment demonstration for CSO LTCP

6
Conventional CSO Wisdom

• Collect convey overflow at the POTW location
• WWOPs plans are important to document/verify how
  you are maximizing flow

7
WWOPs Why Developed

• Important for evaluating facility bypass issues
• Important to manage facility operation during wet
  weather

8

• Approach to Developing WWOPs

9
WWOP Development

• Simple
• Just explain wet weather diversion flow levels
• Advanced
• Explain each step in treatment process
• Purpose
• Role in wet weather treatment
• Max flow/diversion level/rate
• Reason for diversion

10
Approaches to WWOPs Development

• One size fits all
• All plants will achieve specific primary,
  secondary and any additional (i.e., disinfection,
  screening, etc) flow levels
• Plant-specific

11
Approach to Developing WWOPS

• Pre storm preparations (draw downs)
• Operations during storm events
• All throttling
• Manual manipulations of wet weather flows
• Post-storm operations

12

• Strategic Use of WWOPS

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Strategic Use of WWOPS

• WWOPS facilitate disclosure of management of wet
  weather flows
• With permit renewal application
• As part of approved facility OM plan
• Referenced in documentation of the NMC flow
  maximization requirement
• Disclosure sets up NPDES permit shield for
  operation regime

14
Strategic Use

• Disclose and incorporate by reference
• Formal part of facility OM manual
• Expressly identify plan/regime in the permit
• Facilitates subsequent LTCP development,
  including POTW capacity alternatives analysis and
  secondary bypass showing

15
Strategic Use Avoid Allegations of
Non-compliance

• WWOPs are important protect you and your
  organization regarding how you manage wet weather
  flows
• Issues regarding appropriate wet weather capacity
  should be resolved through WWOP
• Especially in plants with manual manipulations
  during wet weather

16
Strategic Use of WWOPS

• Support permit requirements for wet weather flows
• Lower/monitor only percent removal
• Wet weather mass/concentration limits
• Provide one-time comprehensive diversion/bypass
  notice
• Integrate flow maximization requirement with
  other permit requirements (effluent limits)

17

• Conclusions

18
WWOPS Used TO

• Memorialize analysis behind maximization of flow
  strategy
• Memorialize wet weather operations
• Disclose and obtain permit shield for WW
  operations

19
WWOPS Used TO

• Establish baseline for inclusion of CSO-related
  diversions into CSO LTCP
• Support permit authorization for diversions
• Support alternate permit requirements