• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
LTCP meeting 03-02-05

LTCP meeting 03-02-05






Total Views
Views on SlideShare
Embed Views



0 Embeds 0

No embeds



Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
Post Comment
Edit your comment

    LTCP meeting 03-02-05 LTCP meeting 03-02-05 Presentation Transcript

    • Ottawa River Public Meeting #2 – Options Long Term Combined Sewer Overflow Control Plan Input March 2, 2005
    • Discussion Agenda
      • Long Term Control Plan Recap
      • Control Alternatives
        • Common Elements
        • Alternative Differentials
      • Alternative Descriptions
      • Opportunity for Input
    • CSO Control Planning
      • The City must control CSO discharges according to the consent decree
      • Alternatives are being evaluated with respect to their feasibility, associated benefits and costs
      • Public input on alternatives considered is sought in tonight’s meeting
    • Project Timeline
      • The Long Term Control Plan Document is scheduled to be submitted to USEPA in July 2005
      • A review and modification period will follow the plan submittal
      • The work identified in the plan is to be completed by August 31, 2015
    • Ottawa River Combined Area
    • Ottawa River Overflow Frequency Outfall Annual Frequency 61 12 62 25 63 2 64 21 65 14 67 13
    • Ottawa River Overflow Volume Outfall Annual Volume (MG) 61 3 62 52 63 <1 64 40 65 5 67 6 Total 107
    • Alternative Evaluation
      • Alternative evaluation is based on reducing the frequency of overflow to 0 – 12 times a year
      • Total elimination of overflows would only occur in the most costly alternatives
    • CSO Control Options
      • Three basic control options were considered:
        • Storage – holds excess flow until capacity is available
        • Treatment – cleans flow before it is discharged; disinfects and removes pollutants
        • Separation – provides new sanitary or storm sewers so that combined sewers are eliminated
      • Flow reduction / rerouting can enhance the above options
    • Measurable Benefits of CSO Control
      • Reduced frequency of CSO discharge
      • Reduced volume of discharge
      • Reduction in pollutants discharged
      • Better water quality in rivers
    • Alternative Definition
      • General alternatives have been identified for the Ottawa River Area
      • The following are common aspects of the defined alternatives
    • Alternative Common Elements
      • The number of overflow locations would be reduced from the existing 6 to 2
    • Alternative Common Elements
      • Remaining overflow would have less pollutant concentration
    • Alternative Common Elements
      • 1 of the overflow locations would be relatively rare (occurring approximately once a year)
    • Alternative Common Elements
      • The frequency of overflow from the primary discharge location would be reduced
    • Alternative Common Elements
      • The total volume of untreated combined sewer overflow would be reduced
    • Alternative Common Elements
      • Some partially separated areas would be completely separated
    • Alternative Common Elements
      • A number of outfalls would be consolidated
    • Ottawa River Overall Alternative
    • Alternative Options
      • There are several different options that must be considered prior to determining the final alternatives
      • These options include:
        • Location of facilities
        • Use of treatment technology
        • Degree of control
        • Cost
      • Siting location – several potential sites have been identified
      Alternative Options
    • Alternative Options
      • Treatment technology
        • The level of treatment technology may vary
    • Alternative Options – Level of Control
      • Total frequency of untreated discharge vs. cost of various alternatives
    • Selection of Alternative
      • Siting Options
        • Windemere Blvd. – would abandon existing street and use for storage or treatment
          • Advantage: lowest cost, low public disruption.
          • Disadvantage: small site – limits level of control
        • Joe E. Brown Park – would use portion of park for facility siting
          • Advantage: large open area
          • Disadvantage: impacts on public use
        • Old Jeep Plant parking area
          • Advantage: industrial area – minimal public impact
          • Disadvantage: not city-owned property, high cost for sewers
    • Selection of Alternative
      • Technology Selection
        • Storage is high cost to build, but easiest to operate; largest use of site
        • Higher level treatment technology would produce better quality effluent, but would be more complex to operate; overall lower cost than storage; treated discharges would occur from these facilities
        • Separation can accomplish control of CSO discharges; in some locations it can be cost-competitive with other options
    • Selection of Alternative
      • Level of Control Selection
        • The range of level of control is between 0 – 12 overflows per year
        • Most approved plans have overflow frequencies of 2 – 6 per year
        • Water quality benefits are limited if frequency is reduced to 8 per year or less
        • Costs increase exponentially as level of control goes to zero
    • Selection of Alternative
      • Cost
        • The range of cost is large
        • Every decision on level and type of control has a cost implication
        • There tend to be diminishing returns for larger facilities
    • How you can help
      • Provide input on the following alternative elements:
        • Site Selection
        • Technology Preferences
        • Frequency of Overflow
        • Cost
      • Provide other comments and ask questions