conceptual septic system design conceptual development

Conceptual Septic System Design

Conceptual Development

6690 Mitch Owens Road

Ottawa, Ontario

Houle Chevrier Engineering Ltd. • 32 Steacie Drive • Ottawa, Ontario • K2K 2A9 • www.hceng.ca

Submitted to:

1343487 Ontario Ltd.

1718 Lakeshore Drive

Ottawa, ON

K4P 1H1

Conceptual Septic System Design

Conceptual Development


Ottawa, Ontario

October 11, 2016

Project: 64459.01

Report to: 1343487 Ontario Ltd. Project: 64459.01 (October 11, 2016)

ii

TABLE OF CONTENTS

1.0 INTRODUCTION ................................................................................................................ 1

2.0 SEPTIC SYSTEM DESIGN ................................................................................................ 2

2.1 Daily Design Sewage Flow .......................................................................................... 2

2.2 Septic System Design Details ...................................................................................... 2

2.2.1 Type A Leaching Bed ............................................................................................ 2

2.2.2 Septic Tanks ......................................................................................................... 3

2.2.3 Pumps/Controls .................................................................................................... 3

2.2.4 Flow Balancing ..................................................................................................... 3

2.2.5 Tertiary Treatment ................................................................................................ 4

3.0 LIMITATIONS OF THIS REPORT ...................................................................................... 4

LIST OF FIGURES

Figure 1....................................................................................... Conceptual Septic System Plan

Table 1 .......................... Daily Design Sanitary Sewage Flow Based on Conceptual Occupancies

LIST OF APPENDICES

Appendix A

Appendix B

Concept Plan 2

Preliminary Geotechnical Investigation Report


1

1.0 INTRODUCTION

It is understood that a rezoning of the existing property known as 6690 Mitch Owens in Ottawa,

Ontario, is being proposed. In order to obtain the proposed rezoning, a conceptual

development plan has been prepared by Lloyd Phillips & Associates Ltd.

A conceptual septic system design is required in order to demonstrate that a system can be

installed on the subject site in conjunction with the proposed layout plan.

In consideration of the above, our firm has been retained to prepare a conceptual septic system

design. The details of the conceptual system are provided in the following sections and on

Figure 1.


2

2.0 SEPTIC SYSTEM DESIGN

2.1 Daily Design Sewage Flow

The conceptual septic system design provided in this report, includes conceptual details

pertaining to buildings and potential occupants, based on the conceptual site plan prepared by

Lloyd Phillips & Associates Ltd. (see Appendix A).

The Ontario Building Code (OBC) provides information regarding the daily design sanitary

sewage flows (DDSSF) for various site uses. Where multiple occupancy types will be present in

a building, the resulting DDSSFs must be combined for the total DDSSF for the building.

Based on the information provided to our firm, conceptual DDSSFs have been established for

each building and its assumed occupancies (see Table 1), where applicable. Also where

applicable, a breakdown of multiple occupancies for each building is included, such as office

space and 'factory' type area. The maximum unit values provided on Table 1 have been

arbitrarily estimated. Any adjustments to these figures will result in a change in the DDSSF, and

possibly an exceedance of 10,000 litres per day.

It is understood that the total DDSSF for the development is to be kept below 10,000 litres. As

such, conceptual, maximum unit numbers (i.e. office area, employee numbers, ...etc.) for each

occupancy and building are provided in Table 1. The resulting, conceptual DDSSF is 9,994

litres.

Based on details provided to our office, it is understood that the proposed septic system will

receive sewage flow solely from standard plumbing fixtures typical of the noted establishments.

2.2 Septic System Design Details

Based on the information provided in a preliminary geotechnical investigation carried out by

others (see report in Appendix B), the subsurface conditions at the subject site consist of topsoil

over sandy soil with groundwater at or within 150 millimetres of ground surface. It is noted that

groundwater levels will fluctuate seasonally and following precipitation events.

Given the subsurface conditions and the available space, a Class 4 Type 'A' style bed is

proposed (see Figure 1).

2.2.1 Type A Leaching Bed

2.2.1.1 Sand Area

The minimum total sand area for the leaching bed is determined as follows:

A = (Q x T)/400, where

A = min. area of contact between imported sand and underlying soil (m2)


3

Q = Daily Design Sanitary Sewage Flow (9,994 litres)

T = Percolation time (‘T’) of underlying soil. (estimated 20 min/cm, for silty sand

subgrade)

A = (9,994 x 20)/400 = 500 m2

2.2.1.2 Stone Area

The minimum stone area is determined as follows:

A = Q/50, where

A = Minimum stone area (m2)

Q = Daily Design Sanitary Sewage Flow (9,994 litres for conceptual design)

A = 9,994/50 = 200 m2

2.2.2 Septic Tanks

The OBC stipulates that the minimum septic tank operating volume for a commercial occupancy

is three (3) times the DDSSF or 3,600 litres, whichever is the greater volume. As such, the

minimum required operating volume of the septic tank(s) is 29,982 litres. For the purposes of

the conceptual development, this could include one (or more) centralized tanks or individual

tanks located at each of the buildings, in which case the dedicated tanks should be sized based

on the DDSSF for the buildings it will serve. Either option is considered feasible for the purpose

of this conceptual design.

2.2.3 Pumps/Controls

Further to the above, in either case, be it central or dedicated septic tank locations, pumps will

likely be required to transport sewage from the source buildings to the septic system. The pump

chamber(s) will have to be sized to accommodate the DDSSF for the building(s) it will serve.

2.2.4 Flow Balancing

Given that the conceptual development is commercial, sewage flow will occur mainly during

daytime business hours, and possibly at concentrated times during an average workday. As

such, it is recommended that flow balancing measures be implemented into the design of the

septic system. Typically, such measures include the installation of a balancing tank(s) within

which effluent accumulates during the workday, and from which effluent is pumped at an

established and equal rate (i.e. pre-determined volume on an hourly basis) so that the dispersal

of effluent to the septic system occurs over a 24 hour period. This approach ensures that the

septic system does not receive large surges of effluent sporadically, but rather smaller volumes

over equally spaced timeframes. This approach will help alleviate the likelihood of system

failure due to overloading, as well as prolonging the lifespan of the system.


4

2.2.5 Tertiary Treatment

As stated, the conceptual septic system consists of a Class 4 Type 'A' leaching bed. As

stipulated in the OBC, effluent being dispersed to this type of bed must be pre-treated to the

criteria provided under Level IV in Table 8.6.2.2 of the OBC. Several proprietary treatment units

are available and approved for use under the OBC for this purpose.

At the time of final design, consideration should be given to the specific benefits each treatment

system will offer given the particulars of the development. These may include availability,

performance history, upfront cost, maintenance requirements, operating costs, availability of

servicing contractors, warranties, ...etc.

3.0 LIMITATIONS OF THIS REPORT

As stated, the details provided herein are based on conceptual details provided to our firm. The

purpose of this document is to demonstrate that a compliant septic system can be installed at

the subject site in consideration of the conceptual development details.

The final design details for the septic system may vary from those provided herein.

We trust this report provides sufficient information for your present purposes. If you have any

questions concerning this report, please do not hesitate to contact our office.

Matthew Rainville, C.E.T. Senior Technologist P:\0. Files\64400\64459.01\Septic Terrain Analysis\64459.01_RPT01_V01_2016-10-11.docx

1. ALL WORKS TO BE COMPLETED IN ACCORDANCE WITH MUNICIPAL,

PROVINCIAL, AND LOCAL AUTHORITY STANDARDS AND REGULATIONS

WHERE APPLICABLE, AND IN ACCORDANCE WITH ACCEPTED INDUSTRY

BEST PRACTICE.

2. INFORMATION PROVIDED ON THE PLAN IS BASED ON INFORMATION

REASONABLY AVAILABLE AND/OR PROVIDED TO HOULE CHEVRIER

ENGINEERING LTD AT THE TIME OF DESIGN. THE CONTRACTOR/OWNER

IS TO VERIFY THE ACCURACY OF THE INFORMATION CONTAINED HEREIN

REGARDING, BUT NOT LIMITED TO, ELEVATIONS, DIMENSIONS,

SETBACKS, EASEMENTS, UTILITY LOCATIONS AND DETAILS, ...ETC., AND

REPORT ANY ERRORS OR OMISSIONS TO HOULE CHEVRIER

ENGINEERING LTD.

3. THE LOCATION OF ALL OVERHEAD AND UNDERGROUND UTILITIES MAY

NOT BE DISPLAYED ON THIS PLAN AND, WHERE SHOWN, THEIR

POSITIONS MAY NOT BE ACCURATE. IT IS THE RESPONSIBILITY OF THE

OWNER/CONTRACTOR TO LOCATE SUCH UTILITIES PRIOR TO

COMMENCING WORKS. HOULE CHEVRIER ENGINEERING LTD. DOES NOT

ASSUME LIABILITY FOR DAMAGE TO SERVICES, UTILITIES, AND

STRUCTURES DURING CONSTRUCTION OPERATIONS.

4. IT IS THE RESPONSIBILITY OF THE OWNER/CONTRACTOR TO ENSURE THAT

THE PLAN USED FOR CONSTRUCTION IS AN APPROVED AND LATEST

VERSION.

5. DIMENSIONS AND ELEVATIONS DISPLAYED ON THIS PLAN ARE IN METRES.

THIS IS NOT A PLAN OF SURVEY. THIS PLAN IS NOT TO BE SCALED,

ALTERED OR REPRODUCED AND IS INTENDED FOR USE ONLY IN RELATION

TO THE PROJECT FOR WHICH IT WAS PREPARED.

6. THIS PLAN SHOULD BE USED IN CONJUNCTION WITH RELEVANT

DOCUMENTS, PLANS, AND DETAILS PREPARED BY HOULE CHEVRIER

ENGINEERING LTD.

7. THE CONCEPTUAL SEPTIC SYSTEM DESIGN AS PREPARED BY HOULE

CHEVRIER ENGINEERING LTD. MEETS ALL ONTARIO BUILDING CODE

REQUIREMENTS AND MANUFACTURER SPECIFICATIONS IN EFFECT AT

THE TIME THE DESIGN WAS PREPARED.

0 40 80

1:2000

120m

Rev.

Chkd by

Location

Scale

Date

ProjectClient

Houle Chevrier Engineering Ltd.

32 Steacie Drive

Ottawa, ON

Tel: (613) 836-1422

www.hceng.ca

[email protected]

NOTES

Drwn by

64459.01

FIGURE 1

MR AFC

OCT 11, 2016

0

REVISION DATE DESCRIPTION

0 10/11/2016 PLANS ISSUED TO CLIENT.

6690 MITCH OWENS RD., OTTAWA, ON

LOUIS DIRAIMO

CONCEPTUAL SEPTIC

SYSTEM PLAN

M

I

T

C

H

O

W

E

N

S

R

O

A

D

B1

POTENTIAL LOCATION

FOR TREATMENT UNITS,

BALANCING TANKS, AND

SEPTIC TANKS (where

required)

CONCEPTUAL 25 x 20 METRES TYPE

'A' LEACHING BED

(Fully Raised 1.2 metres above ground)

PROPOSED ELEVATION UNDERSIDE OF FOOTING

LEGEND

POTENTIAL LOCATION OF SEWAGE PIPE

PROPOSED BUILDING (refer to Concept Plan 2, appendix A)

A

B2

C

D3

D2

D1

D4

D5

D

2

P:\0. Files\64400\64459.01\Septic Terrain Analysis\64459.01_FG01_V01_2016-10-11.dwg, Conceptual Septic Plan, 10/11/2016 12:28:32 PM

TABLE 1 October 11, 2016

Our ref.: 64459.01

Unit No. Conceptual Occupant

Determining Unit

Type for Primary

Occupancy

Maximum No. of

UnitsResulting DDSF1 from

Primary Occupancy

Determining Unit Type

for Secondary

Occupancy

Maximum No. of

unitsResulting DDSF1 from

Secondary OccupancyTotal DDSF

1 for Unit

2

ARestaurant (paper

service only)Seats 30 1800.0 0 1800.0

B2 Service GarageMax. Employees in

Service Area10 750.0 0 750.0

B1 Auto Dealership Office Area (m2) 415 3311.2Max. Employees in

Service/Other Areas15 1125 4436.2

CMulti-Tenant Light

IndustrialOffice Area (m

2) 105 846.8

Max. Employees in

Factory/Other Areas10 750 1596.8

D1Office for Storage

FacilityOffice Area (m2) 175 1411.3 0 1411.3

0.0 0 0.0

TOTAL 8119.2 1875 9994.2

1 The Daily Design Sewage Flow (DDSF) in litres per day is determined based on provisions within the Ontario Building Code 2012.

2 Where multiple occupancies are within an establishment, the combined DDSF of those occupancies must be utilized.

DAILY DESIGN SANITARY SEWAGE FLOW BASED ON CONCEPTUAL OCCUPANCIES


Page 1 of 1


APPENDIX A

Concept Plan 2

by Lloyd Phillips & Associates Ltd.

C o n c e p t P l a n 2

Project: Re-zoningProperty: 6690 Mitch Owens RoadClient: 1343487 Ontario Inc.File No.: 1622Date: September 14, 2016

Mitch Owens RdAlbion RdSUBJECT SITE

Bank St

Leitrim Rd

30m

30m

14m

50m

15m

14 m

12m

7 m

14m

39m 20m

7m7m 7m

15m

35m

50m

20m

12m

65m

A

B1

C

D1

B2

D2

Refuse Storage72 m² (775 ft²)

Asphalt10,896 m² (117,283 ft²)

Septic Field2,000 m² (21,527 ft²)

Gravel19,880 m² (213,986 ft²)

A -1 Storey | 1 Unit-Floorplate: 360 m² (3,875 ft²)-Use: Restaurant

B1-1 Storey | 1 Unit-Floorplate: 4,150 m² (44,670 ft²)-Use: RV, Automobile, ATV or Heavy Equipment dealership (sales, rental, and service)

B2- 1 Storey | 1 Unit-Floorplate: 525 m² (5,651 ft²)-Use: Service garage, and/or storage for B1

C-1 Storey | Multi-Unit-Floorplate: 1,050 m² (11,302 ft²)-Uses: Light Industrial and/or Retail Store

D1-1 Storey | 1 Unit-Floorplate: 200 m² (2,152 ft²)-Use: Self-storage (front office)

D2- 1 Storey | 4 Units-Floorplate: 600 m² (6,458 ft²)-Use: Self-storage (storage units)

D3-1 Storey | 4 Units-Floorplate: 780 m² (8,395 ft²)-Use: Self-storage (storage units)

D4 & D5-Use: Self-storage (outdoor storage)-Area: 2,822 m² (30,375 ft²)

SepticField

D3

NN

Vista Patrick Private

Proposed Private Roads

ALB

ION

RO

AD

MITCH OWENS ROAD

GREELY10

m

70 m

10m

55 m

50 m

7 m

50 m

15 m

20 m

35 m

15 m

370 m

192

m

40 m

24m

50m

46m

7 m

12m

5m

D4

D5

SWM

7 m 5m

5 m12 m

13m

40 m

7m

11 m

5 m

5 m

6m

3m

Commercial / Light Industrial11,805 m² (127,067 ft²)

Vegetation25,881 m² (278,580 ft²)

Storm Water898 m² (9,665 ft²)

*Dimensions are approximate and not subject to a Legal Survey

ROW (34 m)ROW (34 m) ROW (34 m)

12m

9 m


APPENDIX B

Preliminary Geotechnical Investigation Report

by J.D. Paterson and Associates Ltd., April 7, 1999

experience • knowledge • reliability

geotechnical

environmental

hydrogeology

materials testing & inspection

conceptual septic system design conceptual development

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