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Community Advisory Community Advisory Committee Committee
Long Term Control Plan Update
October 25, 2004
Program UpdateProgram Update
• EPA
• Contractor Pre-Bid Meeting
• September Community Visioning Meeting
Ottawa River AlternativesOttawa River Alternatives
• Ottawa River CSO control alternatives are under development
• Alternative concepts will be presented to the public for initial input on November 18, 2004 at a meeting to be held at Friendship Park
• Today’s presentation is a partial preview of the information to be presented to the public
Assistance neededAssistance needed
• The project team is evaluating alternatives from a regulatory, technical and cost perspective.
• We need input on • What issues are of concern to the public as we
evaluate the options• How to present to the public in a meaningful way
Ottawa River AreaOttawa River Area
Ottawa River Overflow Ottawa River Overflow FrequencyFrequency
Outfall Annual Frequency
61 12
62 25
63 2
64 21
65 14
67 13
Ottawa River Overflow Ottawa River Overflow VolumeVolume
Outfall Annual Volume (MG)
61 2.5
62 52
63 0.2
64 39.9
65 5.3
67 6.1
Type of AlternativesType of Alternatives
• Alternative selection is a combination of performance and suitability considerations. There are a number of types of alternatives.
CSO Control OptionsCSO Control Options
• There are three basic control options• 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
Storage / Treatment Basic Storage / Treatment Basic InformationInformation
• Type of facilities: either concrete tanks or tunnels
• Type of treatment: screening (minimum), potentially disinfection
• Land area required: 3 – 10 acres• Typical siting locations: waterfront property,
parks, other vacant parcels near rivers• Other requirements: some sewer work to bring
flow to the site
Storage FacilitiesStorage FacilitiesStorage alternatives can be below grade as basins or Storage alternatives can be below grade as basins or tunnels. Generally some access hatches or support tunnels. Generally some access hatches or support structures are present.structures are present.
Storage/ Treatment Storage/ Treatment Facilities Pros and ConsFacilities Pros and Cons
• Pros• Most work is limited to one location and the
adjacent areas are not disturbed• Water is either stored (small storms) or partially
treated (large storms)
• Cons• Treatment generally requires construction of a
relatively large building.• Construction activities are generally 2 – 3 years in
duration limiting the use of sites during that period.
Treatment FacilitiesTreatment Facilities
Three large treatment facilities in the Detroit Three large treatment facilities in the Detroit Area. These facilities generally require a Area. These facilities generally require a fairly large building.fairly large building.
Sewer Separation BasicsSewer Separation Basics
• Constructs a new sewer to separate flow
• Generally requires 3 – 6 months to complete work on a street; 1 – 2 years to complete work in an areas
• Generally doesn’t involve land acquisition
Sewer Separation Pros and Sewer Separation Pros and ConsCons
• Pros• Upgrades the sewer system
• Eliminates CSO discharges
• Doesn’t require property
• Cons• May increase total load of pollutants to the
waterways• Disruptive to individual property owner
Sewer SeparationSewer Separation
Sewer separation requires construction of new Sewer separation requires construction of new sewers in areas where a single pipe system existssewers in areas where a single pipe system exists
Flow Reduction / Rerouting Flow Reduction / Rerouting Pros and ConsPros and Cons
• Pros• Addresses problem at the source
• Could be considered best environmentally
• Could reduce basement or surface flooding
• Cons• Generally not adequate to solve the entire
problem• Most disruptive to individual property owner• Administratively intensive program
Flow Reduction / Flow Reduction / Rerouting PhotosRerouting Photos
EPA CriteriaEPA Criteria
• The EPA’s primary concern in other CSO Plans around the country is the frequency at which CSO’s discharge
• EPA generally wants to see control of bacteria
• Other items of concern to EPA• Volume of discharge• Pollutants in discharge• Measureable impacts on waterways
Ottawa River Evaluation – Ottawa River Evaluation – probable storage/ treatmentprobable storage/ treatment
Ottawa River Evaluation – Ottawa River Evaluation – probable sewer separationprobable sewer separation
Siting Issues/ ConcernsSiting Issues/ Concerns
• Consider• Areas of open space (sites), reasonably close to
outfalls• Current use of existing sites & associated impacts
due to construction or long term use• Ownership of sites• “Fatal flaws” such as environmental or geotechnical
issues.• Opportunities for secondary benefit – e.g.
brownfield reuse, coordination with other projects.
Ottawa River Potential SitesOttawa River Potential Sites
• Potential sites• Potential sites have been identified based on location
of open space• Currently evaluating the feasibility of these sites• No decisions have been made about the use or non
use of any site
Ottawa River Potential SitesOttawa River Potential Sites
Ottawa River Potential Sites Ottawa River Potential Sites –Joe E. Brown Park–Joe E. Brown Park
Ottawa River Potential Sites Ottawa River Potential Sites - Jeep- Jeep
Ottawa River Potential Sites Ottawa River Potential Sites – Central Ave.– Central Ave.
Ottawa River Potential Sites Ottawa River Potential Sites – Willy’s Park– Willy’s Park
Storage Sizing RequiredStorage Sizing Required
Comparison of Joe E. Brown & Jeep Facilities: 1998 results
01
2
455
1112
01
3
56
0
10
20
30
40
50
60
70
80
0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0
storage basin volume (MG)
volume of overflow (MGal)
0
2
4
6
8
10
12
14
16
number of occurrences
Joe E. Brown Jeep Joe E. Brown Jeep
Comparison of Joe E. Brown & Jeep Facilities: 5-Year Results
0
1.8
3.6
7
12
13.4
0.21
2.4
4.4
8.4
0
10
20
30
40
50
60
70
80
0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0
storage basin volume (MG)
average annual volume of
overflow (MGal)
0
2
4
6
8
10
12
14
16
average number of occurrences per year
Joe E. Brown Jeep Joe E. Brown Jeep
Storage Size and Overflow Frequency – Ottawa Storage Size and Overflow Frequency – Ottawa River; CSO 61, 62, 65, 67River; CSO 61, 62, 65, 67
Treatment Sizing RequiredTreatment Sizing Required
11.4
9.2
7.06.2
4.83.6 3.0
2.01.2 0.8 0.8 0.8 0.8
0
5
10
15
20
25
30
50 60 70 80 90 100 110 120 130 140 150 160 170
treatment capacity (cfs)
volume of untreated overflow
(MGal)
0
4
8
12
16
20
24
number of occurrences
volume # of events
Treatment Rate and Treatment Rate and UntreatedUntreated Overflow Frequency – Overflow Frequency – Ottawa River; CSO 61, 62, 65, 67Ottawa River; CSO 61, 62, 65, 67
1.3 MG1.3 MG 2 MG2 MG
Impact on FootprintImpact on Footprint
Cost projectionsCost projections
• Cost projections are under development
Evaluations Are ContinuingEvaluations Are Continuing
• Additional cost development and comparison to benefits
• Better definition of potential sites and discussions with property owners/ operators
• Development of tunnel storage option
• More technical evaluations (will support cost assessment)
Public MeetingPublic Meeting
• Objective for Public Meeting• Provide information to the public on the potential
impacts to them during construction/ post construction
• Describe the benefits to the river from various alternatives
• Discuss the public preference for various alternative types (storage/ treatment/ separation)
• Present information on the variation in project cost versus project benefit