city of edmonton residential lot grading guidelines

LOT GRADING GUIDELINES RESIDENTIAL PROPERTIES Introduction The Surface Drainage Bylaw No.11501 came into effect on July 2, 1997. This Bylaw requires that all lots zoned to include single detached or semi-detached housing, developed after 1989, are graded in accordance with an approved Lot Grading Plan. In areas developed prior to 1989 please see “Surface Drainage Problems”. Definition Lot grading is the reshaping or sloping of the land in such a way that surface drainage from rainstorms, snowmelt or groundwater is directed away from the buildings and is controlled in a manner that eliminates or minimizes the impact on adjacent properties. Purpose The purpose of lot grading is to provide good drainage away from buildings for the benefit of property owners. The purpose of the Surface Drainage Bylaw is to regulate lot grading and surface drainage requirements within private properties and City right-of-ways. Lot Grading Plans Lot Grading Plans have been part of the approval process for residential properties since 1989. The plans are required for all new developments and are approved by the Drainage Services branch of the Asset Management and Public Works Department on behalf of City Council. Lot Grading Plans specify design elevations, surface gradients, lot types, swale locations, and other drainage information required for lot grading. A Lot Grading Plan establishes the drainage relationship between adjacent properties and its approval is an effective basis for the control of lot grading. Documentation • Surface Drainage Bylaw No. 11501 • Sewers Use Bylaw No. 9675 • Sewers Bylaw No. 9425 • Alberta Building Code 1997 • City of Edmonton Design and Construction Standards Manual

1 February 2008

Lot Grading Guidelines Residential Properties

2 February 2008

LOT GRADING APPROVAL PROCEDURE The Lot Grading Approval Procedure is usually done in two stages. The Rough Grade Stage is generally the responsibility of the homebuilder and the Final Grade Stage is generally the responsibility of the homeowner. It is the builder’s responsibility to ensure that the downspouts (roof leaders) and the sump discharge are draining correctly. Call Drainage Services, Water and Sewer Servicing at 496-5444 to determine the appropriate site servicing. Rough Grade Stage This stage includes backfilling the foundation walls and shaping of the lot to conform to the approved Lot Grading Plan, within acceptable tolerances. The Rough Grade Approval Procedure should occur within 18 months of the issuance of a building permit for a lot.

• Rough Grade Approval Process

1. The builder has the lot surveyed by an Alberta Land Surveyor, Professional Engineer or Registered Architect who prepares a Plan of Certification of As-built Grades (Lot Grading Certificate).

2. The Lot Grading Certificate is submitted to The City of Edmonton Drainage Services. Digital submissions are preferred and if paper versions are submitted they will be scanned. The builder must provide information for their preferred method of contact to receive a Lot Grading Inspection Report. The methods of contact are: fax, e-mail or mail.

3. A Lot Grading Inspector conducts a site inspection to verify that the lot is graded in accordance with the approved Lot Grading Plan. This is usually done within three working days from receipt of the certificate, depending on workload and weather conditions.

4. An Inspection Report is sent to the builder, indicating that the Rough Grade has been approved or that deficiencies exist.

5. If deficiencies exist, the builder must correct the deficiencies within 60 days and notify Drainage Services for a re-inspection. If the lot grading inspector has requested a re-submission of a Lot Grading Certificate to verify corrections or to provide additional information, a re-inspection can not occur until receipt of the new Lot Grading Certificate.

6. When the Rough Grade is approved, the builder and the property owner are both notified. Additional information, regarding final grading and the approval process, is also sent to the property owner.

NOTE: If a builder or a property owner chooses to proceed directly to final grading, they have the option to bypass the Rough Grade Approval Process and proceed directly to the Final Grade Approval Process.


3 February 2008

Final Grade Stage This stage must be initiated by the homeowner within one year of the Rough Grade Approval. The rough grade has been left approximately 7 to 20 cm below final grade for topsoil placement. The topsoil should be smoothly spread out, compacted and ready for sod, liners, rocks etc. If rocks, wood chips or other decorative material is planned, the clay base (rough grade) must be raised to final grade before placing the decorative material. Rock or wood chips do not make up for the 7 to 20 cm of final grade, since surface water can flow through those materials. The owner of a lot located adjacent to a lake (Stormwater Management Facility), walkway or ravine must comply with the terms and conditions of any registered easement, right-of-way, caveat or restrictive covenant registered in favor of the City of Edmonton.

• Final Grade Approval Process

1. The homeowner has the lot surveyed (on sod or topsoil) by an Alberta Land Surveyor, Professional Engineer or Registered Architect who prepares a Plan of Certification of As-built Grades (Lot Grading Certificate).

2. The Lot Grading Certificate is submitted to The City of Edmonton Drainage Services. Digital submissions are preferred and if paper versions are submitted they will be scanned. The homeowner must provide information on their preferred method of contact to receive a Lot Grading Inspection Report. The methods of contact are: fax, e-mail or mail.

3. A Lot Grading Inspector conducts a site inspection to verify that the lot is graded in accordance with the approved Lot Grading Plan. This is usually done within three working days from receipt of the certificate, depending on workload and weather conditions.

4. An Inspection Report is sent to the homeowner, indicating that the Final Grade has been approved or that deficiencies exist.

5. If deficiencies exist, the homeowner must correct the deficiencies within 60 days and notify Drainage Services for a re-inspection. If the lot grading inspector has requested a re-submission of a Lot Grading Certificate to verify corrections or to provide additional information, a re-inspection can not occur until receipt of the new Lot Grading Certificate. When the final grade is completed by a professional landscaper, the homeowner is responsible to notify the landscaper.

6. When the Final Grade is approved, the owner will be sent an approval report and a copy of the Lot Grading certificate.

Lot Grading Inspection Fees A lot grading inspection fee of $110.00, paid at the time the building permit was issued, covers the cost of rough and final grade inspections for single detached and semi-detached (duplex) housing. Inspection fees are outlined in Schedule A of the Surface Drainage Bylaw No. 11501.


4 February 2008

LOT GRADING REQUIREMENTS The following requirements must be met prior to the issuance of Rough or Final Grade Approval. Any requirements that are not met will be marked as deficiencies on the Lot Grading Inspection Report. Site Servicing Each property must dispose of water from the downspouts and the sump discharge in the manner specified by the site servicing requirements.

• Surface Drainage: downspout extensions or splash pads must be placed under the downspouts and the sump discharge (for lots developed prior to 2006).

• Foundation Service: the sump discharge outlet pipe must be connected to the service. • Storm Service: all downspouts and the sump discharge pipe must be connected to the service.

Design Grades Approved Lot Grading Plans have proposed design grades at specific locations for each lot. The Lot Grading Certificate has as-built elevations taken at the same locations. • Acceptable as-built tolerances (from design grades) :

Rough Grade: Between 7 cm and 20 cm below final grade for clay

Example: Design Grade 682.25 m, Existing Grade 82.10m = 15cm below design grade.

Final Grade: Between 0 cm to 10cm below final grade for topsoil (black dirt)

Note: “0” is at approved design grade. Example: Design Grade 682.25 m, Existing Grade 682.20 m = 5 cm below design grade.

Between – 10 cm to + 10 cm above or below final grade for finish landscaping (sod,

concrete) Example: Design Grade 682.25 m, Existing Grade 682.30 m = 5 cm above design grade.

Note: At Final Grade, the surface elevation below the decorative rock, washed rock or wood chips, must be within the tolerance.

• The Lot Grading Inspector has the discretion to accept elevations that are not within tolerance when the following conditions occur:

The landscaping is graded to match an existing fence, walkway, lake, park, curb, sidewalk, road or

lane and there is no impact on the surface drainage. The landscaping is graded to match an adjacent property and it appears to the Lot Grading Inspector

that there is positive on-site surface drainage.


5 February 2008

A proposal is submitted to revise the design elevations on the approved Lot Grading Plan to existing elevations, providing that there is no negative impact on surface drainage and any affected property owners agree to the revision.

Minimum Grade from Foundation Walls A sloped surface is required to effectively drain water away from the foundation walls, including areas under steps and decks. This will greatly reduce the risk of surface water entering the basement during rainfalls or snowmelt (See the Lot Grading Detail drawings for more information).

• Minimum grade requirements:

10% for the first 2.0 m – Minimum 20 cm drop for final landscaping. 0.75% for concrete, asphalt or other impervious surface treatment.

Drainage Swales Drainage swales are shallow sided, sloped ditches intended for the conveyance of surface runoff. Grading of swales should be in accordance with the approved Lot Grading Plan. Drainage swales are usually located on the common property lines and on lots that drain from rear to front, a swale is located in the back yard. Swales on a common property line must provide a minimum of 15 cm of unobstructed width within each property. Swales convey surface runoff to the nearest street, lane, dry pond or stormwater management lake. Due to the topography of some neighbourhoods, approved lot-to-lot drainage may occur. On some lots, an easement or right-of-way is registered to allow for the construction of a concrete or a grass drainage swale. Easements are shown on the approved Lot Grading Plan and must be displayed on the Lot Grading certificate.

• Minimum swale slope requirements for drainage swales:

1.5% for a grass drainage swale 0.75% for a concrete drainage swale

Backfill at Back of Concrete Walks or Paved Lanes To reduce water infiltration into the granular base of concrete walks and paved lanes, non-granular backfill must be placed to the top (the surface) of the concrete or asphalt. This will enhance the long term performance of the walk or lane by preventing water infiltration through the granular base. Downspouts The downspout must have an elbow and a hinged extension or concrete splash pad. The downspout elbow should be directed away from the foundation walls towards the drainage swales along the common property line. Downspout extensions or splash pads must not project past the property line. Hinged downspout extensions are not recommended as they are easily damaged or left in the up-position. However, hinged extensions are acceptable provided they do not extend on to adjacent property.


6 February 2008

• Minimum distance from property line:

15 cm from an adjacent private property 30 cm from an adjacent City property

Sump Pump Discharge The sump pump is part of the building’s foundation drainage system and has been a requirement since 1988. The sump pump discharges groundwater from the weeping tile to the ground surface or directly to the Storm or Foundation Sewer service. For lots developed prior to 2006, if the sump pump discharges to the ground, then it is important to provide a splash pad or a flexible hose at the discharge point. This minimizes soil erosion at the foundation wall and the re-circulation of the groundwater back to the weeping tile. The flexible hose or splash pad should be directed to the drainage swales and not onto an adjacent property. The sump pump discharge hose should be disconnected during the winter months to prevent freezing in the hose. Beginning in 2006, all new developments involving single detached, semi-detached or duplex houses must provide “foundation drain discharge collection systems”. These properties must connect the sump discharge outlet to the foundation service. Splash Pads Splash pads convey roof water and groundwater past the foundation excavation zone and away from the foundation walls. They minimize soil erosion and recycling of water through the foundation drainage system. The recommended standard concrete splash pad is 30 cm x 107 cm. Please refer to the splash pad detail at the end of these guidelines. • Where direct connections to a Storm or a Foundation sewer service are not available, splash pads are

to be placed:

Underneath all downspouts draining onto soft landscaping (sod, topsoil and/or gravel). Underneath the sump pump discharge outlet where it is draining onto soft landscaping (sod, topsoil

and/or gravel). Lot Grading Certificates Where there is an approved Lot Grading Plan, a Lot Grading Certificate is required for an approval of Rough and Final Grade. For in-fill development, where there is no approved Lot Grading Plan, submission of either a rough or final grading certificate is required to validate that the grading meets the requirements of the Surface Drainage Bylaw and the Lot Grading Guidelines. Lot Grading Certificates for Rough and Final Grade display the following information:

Certification by an Alberta Land Surveyor, Professional Engineer or a Registered Architect Name of the Company that produced the Certificate Property Information: Legal Description and Municipal Address Surface Condition of the Lot: i.e. Clay, Topsoil, Sod, or Landscaped Note indicating that the Grading is subject to the approval of the Local Authority


7 February 2008

Design and existing elevations referenced to metric geodetic datum, with an asterisk designating existing elevations that exceed the grade tolerance

As-built elevations of structures such as: retaining walls, sidewalks, driveways, fences As-built elevations of the adjacent property, if landscaped, at the design elevation locations Foundation grade elevations with an additional elevation 2-3 metres from the back of the house As-built property-line (swale) elevations opposite the corners of the building, for locations that are

more than 3 meters from a design point Elevation of as-built high point on split grade lots, if location is different from the design Date of Survey Scale of drawing House layout North Arrow Drainage Easements and Right-of-Ways Detailed Surveys for lake lots require the location and elevation of structures or features within the

Maintenance and Overflow Area Lot Orientation is Portrait, with the rear of the lot at the top of the page and the “FRONT” of the lot

labeled Name of the applicant and the information required to send inspection reports or grading approval

i.e. Mail, fax number or e-mail address Lake, Ravine or Top of Bank Lots Properties located adjacent to Stormwater Management Lakes, ravines or top of banks that have a right-of-way, easement or restrictive covenant registered in favour of the City of Edmonton, require the Lot Grading Certificate to display the location and elevation all features constructed within the affected area. Features to note include, but are not limited to: decks, fire-pits, ponds, paths, bridges, retaining walls, buildings, raised gardens or unusual grade alterations. Inclusion of these details will enable Drainage Services to evaluate the impact these features have on drainage and water storage requirements. This information must be included on the Lot Grading Certificate prior to the request for an inspection or re-inspection. Sprinkler Systems Irrigation systems, an automatic or manually operated system of pipes and sprinkler heads or drip hoses installed in place to supply moisture to the ground, are prohibited on any slope. Extreme Grade Differential Lot Grading with substantial grade differences, from the side of the house to the rear of the house, can occur on Walk-Out basements. Grading for these homes may require a retaining wall or some form of grade stabilization at the transition point at the rear corner(s) of the house. The grading of the drainage swale down the common property line follows the approved lot grading plan for the area. The first property that is graded within tolerance sets the precedence for the adjacent properties to match (with or without grade separation). This situation can occasionally occur on non walk-out lot types as well. Any retaining wall that exceeds 0.60 m in height, or is attached to the house, should be of an engineered design and construction. For design requirements and permits, please contact the City of Edmonton, Planning and Development Department at 496-3100.


8 February 2008

Lot Grading Maintenance Once Final Grade Approval has been issued, it is the property owner's responsibility to maintain the surface grading in perpetuity. The City of Edmonton may, at any time, require maintenance on the surface grading if alterations or settlements result in surface drainage problems. Enforcement Reports, Letters or Notices will be utilized to convey notification of impending enforcement to an owner, builder, or developer. Subsequent fines may then be imposed for those properties that do not comply with the Lot Grading Guidelines or the Surface Drainage Bylaw No. 11501. In most cases, notification is sent to the current registered property owner. This bylaw is enforceable for all properties. In deciding whether to enforce this bylaw, the City may take into account practical concerns, existing conditions, and complaints or inquires. Each property owner in the City is responsible for their own lot grading. The City of Edmonton does not provide any funding for repairs to surface grading See “Surface Drainage Problems” for information on how to deal with drainage problems in areas developed prior to 1989. IN-FILL HOUSING Grading Approval and lot grading certificates are a requirement for in-fill developments. Site inspections and grading approvals can be arranged by submission of a Lot Grading Certificate to Drainage Services FOR MORE INFORMATION Lot Grading Details and Drawings

Single Family and Duplex Residential Lot Types A, B, C, D, & W

Pamphlet Series

“How to Keep Your Basement Dry This Summer” A Quick Guide to Effective Home Drainage

“Roof and On Lot Drainage Guide” Ensure Your Lot Drains Effectively

“Flood-proofing Devices - Inspection and Maintenance” A Small Investment to Prevent Basement Flooding


9 February 2008

“Sump Pumps” An Information Guide

“Lot Grading In-fill Housing Development” “Lot Grading Lake Lots and Top of Bank Lots” “Lot Grading Inspections”

Residential Properties “Lot Grading Inspections”

Residential Properties “Flood Proof – Flood Prevention Program”

The Homeowner’s Guide to Flood Prevention “Flood Proof – Flood Prevention Program”

Sump Pump Guide “Flood Proof – Flood Prevention Program”

Flood Prevention Tips for Homeowners “Flood Proof – Flood Prevention Program”

Flood Prevention Check-up “Clearing the Air”

Odour Control at the Gold Bar Wastewater Treatment Plant “Edmonton’s Sewer Odour Control”

An Information Guide “Drainage Inspections”

Industrial, Commercial and Institutional “Living Near Urban Lakes” “Treat it Right Storm Water”

Teachers Guide “Treat it Right Wastewater”

Teachers Guide CONTACT INFORMATION Telephone Numbers

Asset Management and Public Works Department, Drainage Services 496-5576 – Lot Grading Information and Assistance (8:00 am - 4:30 pm Monday to Friday) 496-5500 – Lot Grading Recorded Procedures, Message and Request Line (24 Hours) 496-5543 – Main Floor Reception 496-2865 – Lot Grading Fax 496-5444 – Water and Sewer Servicing Information 944-7777 – Flood Proof – Flood Prevention Program 496-1717 – Drainage and Sewer Trouble (24 Hours)


10 February 2008

Mailing Address

City of Edmonton Drainage Services Lot Grading Main Floor, Century Place 9803 – 102A Avenue Edmonton, Alberta, T5J 3A3

Internet Addresses www.edmonton.ca www.edmonton.ca/floodprevention

E-mail Address [email protected]

(2008 Residential Guidelines.doc)

http://www.edmonton.ca/

http://www.edmonton.ca/portal/server.pt/gateway/PTARGS_0_2_276_216_0_43/http;/CMSServer/COEWeb/household/flood+relief/

mailto:[email protected]

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city of edmonton residential lot grading guidelines

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