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	Corporate Report
DEPARTMENT/	Infrastructure & Operations
DIVISION	Engineering	REPORT NO.	2012.119
DATE PREPARED	July 11, 2012	FILE NO.
MEETING DATE	July 30, 2012
SUBJECT	City of Thunder Bay Storm Water Master Drainage Study and Residential Drainage Assistance Program - Update

RECOMMENDATION

With respect to Report No. 2012.119 (Engineering), we recommend that the proposal submitted by Hatch Mott MacDonald (ENL) dated July, 13, 2012 be accepted at an upset limit cost of $300,704.30 inclusive of HST, to undertake a Neighborhood Master Stormwater Drainage Study for designated areas as listed in this Report and develop a Residential Drainage Assistance pilot project;

AND THAT Administration be authorized to negotiate a formal engineering agreement with Hatch Mott MacDonald (ENL) on the basis outlined in this report and in accordance with Corporate By-Law 113-2011 - “Supply Management By-law” Article 5.02 Emergency Method for Goods and Services over $60,000;

AND THAT the proposed Residential Drainage Assistance Program (RDA), including subsidies for private property drainage improvements, as outlined in this Report be approved in principle;

AND THAT Administration proceed with the implementation of Phase I and Phase II of the RDA program and report back prior to the 2013 Budget on the full implementation of the program including ongoing capital and operating budget requirements;

AND THAT Administration be directed to negotiate with ECO Superior to develop and administer an ongoing Residential Drainage Assistance subsidy program;

AND THAT the General Manager of Infrastructure and Operations report any circumstances to City Council should variations in the agreement occur;

AND THAT the Mayor and Clerk be authorized to sign all documentation related to this matter;

AND THAT any necessary By-laws be presented to City Council for ratification.

Administration is seeking Council approval to retain the services of an engineering consultant firm to undertake a Stormwater Drainage Master Study for the areas impacted most by the May 27 and May 28, 2012 storm event and to develop a pilot project to assist residential property owners to address drainage issues on their property.

A Neighbourhood Master Stormwater Drainage Study will include a comprehensive review of the existing sewer system in specific designated areas and will provide alternative solutions to assist in preventing residential basement flooding. A long term capital program will be developed for storm water management and pollution prevention control in the designated areas.

A Residential Drainage Assistance pilot project will also be tested in a smaller neighbourhood (i.e. 10 -12 homes) in one of the designated areas. This program if successful could be used throughout the City to address similar issues on residential properties.

As per the recommendation in Corporate Report 2012.107 (City Manager’s Office), an independent engineering assessment of the Atlantic Avenue Water Pollution Control Plant will be undertaken to analyse the flooding of the Plant for the purpose of repair and recovery work and for future action to prevent future Plant flooding. Administration has procured the services of CIMA partners in excellence to undertake the study. CIMA is a multidisciplinary, employee-owned Canadian engineering firm that was incorporated over 20 years ago. The firm has more than 2,200 staff with 33 offices across Canada and internationally, and offers a full range of services in the areas of water and wastewater engineering, environment, energy and transportation. All of CIMA’s offices are ISO 9001 certified.

The objectives of the study are to:

1. To complete an independent assessment of the flooding at the Thunder Bay WPCP including flows to the facility, a hydraulic assessment of unit processes and identification of points of entry of flood water and/or sewage to the pumping station, other unit processes and tunnels in the plant.

2. To review alternative remediation approaches and develop conceptual design requirements and costs to reduce the future risk of flooding due to outside influences (i.e. extreme rainfall/snowmelt, high river level, site flooding) and internal plant hydraulics.

3. To provide a comprehensive report presenting all findings and recommendations to the City.

CIMA has commenced with the study and administration anticipates that it will take approximately 3 – 4 months to complete the above work.


Neighbourhood Master Stormwater Drainage Study (NMSDS)


Administration has prepared an outline for a Terms of Reference to provide guidance and direction to a consulting engineering firm to undertake a detailed stormwater drainage study in those areas that were most directly impacted by the May 27 and 28, 2012 storm event.

The consultant will review, investigate and monitor the existing sewer systems to establish location, magnitude and causes of basement flooding within the designated areas. Through a consultative two-way process with residents in the designated areas, the consultant will determine the history of basement flooding and the type of basement flooding in each area.

A monitoring program will be designed to collect local flow data to be used to verify model parameters associated with wet weather responses. The storm sewer system model for the designated areas is tested and is improved through calibration to reflect local conditions and real data is used to refine the basement risk assessment to determine if further capital works are required. Over a period of one year flow meters will be installed in sewers to determine response to wet weather and verify model parameters.

With the use of hydraulic models the consultant will identify problems related to stormwater and surface drainage run off within the designated areas. Various alternative remedial measures will be investigated to help prevent and reduce basement flooding and a prioritized implementation plan for capital projects will be presented for budget approval.

As the long term remedial measures will not be finalized for the next year Capital Budget, short term projects are anticipated to be included in the 2013 Capital Budget. The Engineering Division is also conducting an analysis of the major problem areas as related to basement flooding and inspecting storm sewer outfalls. Administration is reviewing potential improvements to incorporate into the 2013 Capital Budget.

The designated areas to be studied as part of the consultant’s assignment are highlighted in Attachment ‘A’, ‘B’, ‘C’ and ‘D’.

Residential Drainage Assistance Program (RDA)


Administration has reviewed a number of existing programs in other Canadian municipalities that are directed at providing assistance to home owners with respect to storm drainage related matters.

Subject to Council approval of this Report, over the next few months a pilot program will be designed to provide assistance to residential property owners regarding drainage issues. The program would be in two phases. Phase I would entail the City retaining the services of a professional engineer specializing in drainage, to undertake a site specific pilot study of an affected smaller neighbourhood area (i.e. 10-12 homes). The initial phase would consist of a review of the following:

· lot grading and identify low points

· drainage paths including swales

· obstruction to drainage (i.e. sheds, trees)

· roof down spout location

· storm lateral review – may recommend camera inspection

· sanitary lateral review – may recommend camera inspection

· weeping tile connection

· sump pit and pump

· backflow prevention

Administration would meet with the engineer to discuss the information gathered and create a final report with recommended mitigation measures and a discussion held with the affected resident. It is estimated that an assessment of a ten properties would cost $10,000.00 or approximately $1,000.00 per property.

Phase II would include implementing the Phase I report’s recommendations. In this phase, the City would be responsible for any improvements required within the City’s road allowance through proposed Capital Budget funding. The resident would be responsible to undertake any work on private property. However, the costs for the work on private property will be partially offset through a shared cost program where the City directly subsidizes a portion of the cost. Based on the review completed of other Cities, a proposed City of Thunder Bay subsidy program would be as follows:

· back-flow prevention valve – 50% of the invoiced cost up to a maximum of $1,250.00 including labour, materials, permit and taxes

· sump pump – 50% of the invoiced costs up to a maximum of $1,750.00 including labour, materials, permit and taxes

· back-flow prevention valve and sump pump – 50% of the invoiced cost up to a maximum of $3,000.00 including labour, materials, permit and taxes

· disconnecting weeping tile from sanitary lateral – 100% up to a maximum of $500.00 including labour, materials, permit and taxes

The City will determine the eligibility of properties that meet the requirements for this subsidy as listed below:

· subsidy available only to existing homes in the designated areas. Note, all homes impacted by the May 28, 2012 flood (basement flooding) would be eligible

· property must have its eavestrough downspouts properly disconnected from City sewer system

· a plumber licensed by the City of Thunder Bay must be hired to install the back-flow prevention valve and a qualified contractor to undertake all other work

· a building permit and approved inspection must be obtained for back-water valve installations

Administration is considering facilitating the RDA with the assistance of EcoSuperior who has undertaken this type of service for the City in the past. For the 10–12 properties to be included in the pilot program, total City subsidy may top off at $42,000 plus administration costs subject to the homeowner agreeing to cost share the work. A rebate is provided as a credit on the homeowner’s water account or a rebate cheque is provided to the homeowner.

The Neighborhood Master Stormwater Drainage Study (NMSD) and the initial phase of the Residential Drainage Assessment (RDA) will be undertaken by an engineering consultant specializing in storm water management at an estimated cost as follows:

· NMSD Study - $289,404.30 (inclusive of HST)

· RDA Phase 1 - $11,300 (inclusive of HST) for pilot project

· RDA Phase 2 – to a maximum of $3,500 per home (for the pilot study 12 homes x $3,500 = $42,000.00

· Wet weather monitoring equipment and data collection by city staff - $60,000.00

The Engineering Division in conjunction with the Stormwater Management consultant will prepare an interim report early in 2013 for short term infrastructure improvements in one or two of the designated areas with anticipated incremental capital budget implications in 2013 of between $1,000,000 and $1,500,000.

Once the NMSD study is completed for the designated areas a long term implementation plan and capital cost estimates will be presented to Council.

Similarly, once Phase I and II of the RDA program have been completed, Administration will report back on the 2013 Budget implications of implementing the program on an ongoing basis.

It is concluded that an engineering consultant should be retained for the NMSD study and RDA pilot project at an upset cost limit of $289,404.30 and $11,300 respectively.

It is further concluded that Administration negotiate with EcoSuperior to develop and administer an ongoing Residential Drainage Assistance subsidy program.

It is further concluded that Administration include up to $1,500,000.00 for consideration and final approval by Council in the proposed 2013 Capital Budget for interim improvements to the storm water system in a designated study area as described in this report.

On June 18, 2012 the City Manager’s Office presented Report No. 2012.107 (City Manager’s Office) to Committee of the Whole – City of Thunder Bay Flood Disaster – “Go Forward” Strategies and Actions. As a result of the May 27 and 28^th, 2012 unprecedented storm event the City was declared a disaster area by the Minister of Municipal Affairs and Housing. The report discussed issues related to flooding and introduced proposed strategies and actions for consideration by Council related to municipal infrastructure and private property owners with flood prevention measures. Four resolutions were presented to Council and this report is a follow up to the items in the resolutions.

Attachment ‘A’ – Map of Designated Area 1
Attachment ‘B’ – Map of Designated Area 2
Attachment ‘C’ – Map of Designated Area 3
Attachment ‘D’ – Map of Designated Area 4