215 Sanders Street, Unit 1 (613) Prescott Street, Unit 1 P.O. Box 189 Kemptville, Ontario K0G 1J0 FAX: (613)

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1 Civil Geotechnical Structural Environmental 215 Sanders Street, Unit 1 (613) Prescott Street, Unit 1 P.O. Box 189 Kemptville, Ontario K0G 1J0 FAX: (613) December 17, Ontario Inc. 242 Wall Road Navan, Ontario K4B 1J3 Attention: Mr. Jacques Patenaude and Luke Brazeau SERVICING BRIEF PROPOSED RESIDENTIAL SUBDIVISION DEVELOPMENT PART OF LOT 6, CONCESSION 11, MER BLEUE ROAD AND WALL ROAD VILLAGE OF NOTRE DAME-DES-CHAMPS CITY OF OTTAWA, ONTARIO Mr. Jacques Patenaude and Luke Brazeau of Ontario Inc. have retained the services of Kollaard Associates Inc. (Kollaard) to prepare the servicing design and brief for the proposed Residential Subdivision Development at the south side of Wall Road and east side of Mer Bleue Road in the Village of Notre-Dame-des-Champs, City of Ottawa, Ontario. The proposed Residential Development occupies a total area of about 11 hectares. It is planned to develop the site for 39 single family residential lots and one existing single family residential lot. The development is to include underground services consisting of municipal water and storm sewers. Sanitary services will be provided by onsite Class 4 septic systems designed in accordance with Part 8 of the Ontario Building Code. This brief identifies the servicing requirements and addresses the feasibility of utilizing existing municipal infrastructure to accommodate any additional demands placed on the system as a result of the proposed development. SANITARY SERVICES The proposed development will not be serviced with sanitary sewers. Sanitary sewage requirements will be met with the use of onsite septic systems designed in accordance with Part 8 of the Ontario Building Code. The sanitary flow requirements for a single family residential dwelling based on Part 8 of the Ontario Building Code are a function of the size of the proposed dwelling, number of bedrooms within the dwelling and number of fixture units within the dwelling. A sample Residential Sewage design flow calculation sheet is attached. Professional Engineers Ontario Authorized by the Association of Professional Engineers of Ontario to offer professional engineering services.

2 December 17, File No For the purposes of estimating the envelope of the proposed septic system in order to facilitate the grading and lot layout designs, the proposed dwellings were assumed to have a living space of 232 square metres (2500 square feet). Each dwelling was assumed to have 4 bedrooms, 3 full bathroom groups, as well as a domestic clothes washing machine and dish washer. A typical requirement for residential dwelling lots serviced by an onsite septic system is to ensure that there is sufficient space available on each lot for a conventional septic system. However, it is considered that the construction of a conventional septic system will result in an unacceptably high landscape grade raise adjacent the proposed dwelling due to its height. In order to reduce the height of the septic bed, thereby reducing the landscape grade raise requirement, it is proposed to use a tertiary septic system in combination with an area bed. This will result in a height reduction for the septic system from 1.8 metres for a conventional system to 1.35 metres for the tertiary system. From the preliminary calculations, the onsite septic systems have a minimum area requirement of 120 square metres. The septic beds were designed assuming fully raised conditions, that is an imported sand mantle with a minimum length of 15 metres would be required to distribute the sanitary flow to the underlying subgrade. The septic bed areas indicated on the proposed grading and servicing drawings have areas of between 207 and 280 square metres as required to support the requirement for the sand mantle. STORMWATER DESIGN In general, the stormwater management plan consists of collecting the stormwater runoff from the site and controlling the release rate such that the post-development release rates do not exceed the predevelopment maximum flow rates for the 5 year pre-development design storms based on existing site conditions for all storm events to and including the 100 year design storm events. In addition the proposed stormwater management design will provide an enhanced level of treatment for the runoff from the site as well as the offsite areas contributing runoff to the site. Specifically, stormwater will be directed by means of sheet flow and swales to catch basins within roadside swales which outlet to a storm sewer beneath the streets of the proposed subdivision. The storm sewer will consist of 525 to 750 mm diameter double wall HDPE pipe and will be utilized to convey and store stormwater runoff. Additional storage will be provided by means of ponding within the roadside swales. Details of the dry pond are included in this letter. The post-development runoff release rate will be controlled by means of a Hydrovex Inlet Control Device placed within a storm manhole at the outlet of the subdivision. Enhanced treatment will be provided by means of a Stormceptor STC 4000 treatment unit or approved alternative treatment device. The treatment unit is designed to accommodate the runoff originating on the site as well as runoff originating on the offsite catchment areas. For further information refer to Kollaard Associates Stormwater Management Report The storm sewer design calculation tables are attached for the post development flow. The storm sewer system was designed to have sufficient capacity to accommodate the postdevelopment 5 year storm event under gravity flow conditions.

3 December 17, File No WATERMAIN DESIGN The design consists of about 971 m of 200 mm diameter watermain complete with 7 fire hydrants and appurtenances with 39 service connections as follows: Street From To Length # of Service # of Fire m Connections Hydrants Street Street Street Street Totals The proposed 200 mm diameter watermain will be looped between Jade Lane and Wall Road along Street 2 and between Mer Bleue Road and Street 2. These watermains are connected to the municipal waterworks system which is part of the City of Ottawa System. The water demand for the proposed development was calculated based on the City of Ottawa Water Distribution Design Guidelines as follows: Residential occupancy = 3.4 persons per three bedroom home 39 homes of three bedrooms x 3.4 pers./unit = persons Total occupancy = 133 persons Residential Average Daily Demand = 350 L/c/d. Average daily demand of 350 L/c/day x 133 pers = m3/day or L/s Maximum daily demand (factor of 2.5) is L/s x 2.5 = L/s Peak hourly demand (factor of 2.2) = L/s x 2.2 = 0.26 L/s Fire demand is the volume of water a system must be capable of providing, above and beyond the usual demands of the community, for the purpose of fighting fire based on the volume of water required to douse a fire of a certain type. The existing closest hydrants are located along Wall Road, Mer Bleue Road and Jade Lane. The 2008 version of the MOE guideline for fire flow requirement table is manipulated for analyzing the demand for the proposed development Table 6.1 Fire flow requirement for small communities(adapted from MOE, 2008) Population Suggested fire flow (L/min) Suggested Duration (hr) , , ,800 Suggested Volume (L)

4 December 17, File No The fire flow is to be provided through the proposed fire hydrants, which will be installed at maximum spacing of 120 m throughout the service area. According to the AWWA, hydrants should only be installed on pipes with diameter above 150mm that have been designed to provide fire flow. UTILITIES Hydro, Bell, Cable and Gas will be provided in a Four Party underground trench. All servicing requirements will have to be approved by the City of Ottawa and the relevant utility providers. CONCLUSION The existing municipal water infrastructure is adequate to accommodate the proposed subdivision development. The construction of onsite septic systems to service the proposed development is feasible. The proposed storm sewer system is sufficient to accommodate the proposed subdivision We trust that the information provided is sufficient for your present requirements. Do not hesitate to contact our office should you have additional questions or concerns. Sincerely, KOLLAARD ASSOCIATES INC., Dec Steven dewit, P.Eng.

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