Residential Lot Grading Requirements

The information contained herein serves to confirm lot grading submission requirements, lot grading design criteria and approval processes as outlined in the City of Brockville’s Drainage Bylaw 033-2004 (Bylaw to Amend Bylaw 113-91) Being a Bylaw to Regulate Drainage in the City of Brockville.

General:

Lot grading shall be designed to conform in principle to the site Storm Water Management Plan and Master Grading Plan. The plan shall show the existing and proposed final grades for each lot and block within the plan. In addition, the design shall adequately provide for any necessary interim drainage in order to limit flood risk, having regard for the pre-development overland flow patterns. The term “flood risk” is to be interpreted as a risk of personal liability and/or property damage as a result of flooding brought about by the alteration of pre-development flows and/or flow patterns. The design shall make provision for such interim measures, grading culverts etc. as may be required to promote positive drainage.

All Lot Grading issues and concerns that may arise are the responsibility of the Owner, on which the development/Site Alteration is taking place. It is the responsibility of the Owner to work with their Lot Grading Professional to resolve any Lot Grading issues/concerns that may arise.

Lot Grading Submission Requirements:

Note: All submissions pertaining to lot grading are to be submitted to the Building Department, through the CloudPermit portal.

1. Lot Grading and Drainage Plan submissions accompanying all Phase 1, Revised Phase 1, and Final Grading applications are to be prepared by an Ontario Land Surveyor or a Professional Engineer “P. Eng.” Licensed in the Province of Ontario.
2. The site shall be surveyed, and a plan shall be prepared by an Ontario Land Surveyor. Or P. Eng. Licensed in the Province of Ontario. All plans shall be prepared using “Best Engineering Practices”.
3. Where the property to be developed has an approved Master Grading Plan and Drainage Plan, the Phase 1, Revised Phase 1, and Final Grading, lot grading and drainage plans will be required to correspond with the elevations, grades and design criteria illustrated on the approved Master Grading Plan and Drainage Plan.
4. On any lots that have had the previous building removed for any reason and a new building is proposed or the property to be developed does not have an approved Master Grading Plan and Drainage Plan, due to it being an “in-fill” lot or a lot located in an area developed prior to requirements for a Master Grading Plan and Drainage Plan, there will be a requirement to have a Lot Grading Plan completed and accepted by the City.
5. All Phase 1 plans approved and submitted by a Lot grading Professional that meet City standards shall be accepted by the City. There shall be no deviations from the Master Grading Plan in any way. The Final Grading submission shall be submitted by an Ontario Land Surveyor or a Professional Engineer “P. Eng.” licensed in the Province of Ontario.

The following design criteria and guidelines shall be provided as a minimum.

Lot Grading Design Criteria:

Phase 1 and Revised Phase 1 grading plan

• All elevations and measurements to be in metric units
• Survey completion date, signature and stamp of agent
• 11”x17” sheet size (minimum)
• Drawing scale = 1:200
• Revision block including revision number, date, and revision title
• Provide the date and revision correlated with the Master Grading Plan used
• Street Name, Lot number and civic address if available
• Geodetic benchmark information (location and elevation), and North Arrow
• Location of property lines, front, side and rear setback measurements, and lot dimensions
• Location and elevations for all existing lot corners, swale tie-ins to sidewalk or curb lines, corners of adjacent property buildings, drainage facilities, window openings, window wells, swimming pools, hedges, fences, retaining walls and any other appurtenances that may affect drainage
• Proposed locations and elevations at all breakpoints, building corners, garage floors, patios, basement window openings at or below grade, top of window wells, walkout door sill elevations, elevations at the property lines or in swales adjacent to the building corners, top of foundations, finished floors, decks, porches, retaining walls, infiltration trenches with outlet elevations, drainage facilities, fences, swales, center line of the street, curb, sidewalk, and all other items affecting lot drainage
• Location and top of grate elevations of any drainage structures located on private property (If Applicable)
• Proposed slope arrows with gradients showing the gradients of swales, slopes, driveways, patios, and graded areas
• Surface slopes to be a minimum gradient of 2% and 3:1 maximum
• Provide a drainage apron around the perimeter of the building displaying positive drainage away from the building, 2% minimum gradient and 150 mm in vertical depth
• Surface swales are to have a minimum longitudinal gradient of 2%, if less than 2% an infiltration trench shall be designed with an appropriate outlet
• Drainage swales are to have a minimum depth of 150 mm, preferably 200 mm in depth. Swales shall be sized to convey the surface runoff volumes present for the location
• Rear yard swales located on the property line between properties shall have a minimum depth of 200 mm, preferably 300 mm in depth
• A swale shall be required on all property lines to direct surface drainage and prevent surface run-off onto adjacent properties
• For new subdivisions the City recommends that swales be completed on the property lines, this may require work beyond the property line, this will assist with future grading on adjacent properties, especially if they are completed in different phases
• Natural drainage patterns and channels must be respected. Landowners must accommodate runoff from upgradient properties. Surface runoff water shall not be discharged onto adjacent lands in a concentrated amount, nor shall it exceed the pre­development flows
• Major system drainage is to be directed to public lands
• Driveways slope to be a minimum 2%, with 10% maximum upgrade and 8% minimum downgrade
• Retaining walls, curbs, infiltration trenches or other adequate approved drainage facilities maybe be used in lieu of swales
• All window wells are to be a minimum of 150 mm above final grade
• Sufficient information regarding adjacent properties to confirm conformance with the drainage by-law with respect to drainage to those properties
• Six (6) meter easement to be provided for any rear or side yard ditch inlets with storm sewer connection to the City storm system that are to be maintained by the City
• The maximum depth of ponding resulting from any storm event shall not exceed 300 mm.
• Retaining walls are to be shown on the plan where the maximum lot slope is exceeded. An engineer’s seal may be required dependent on the height of the wall. Where applicable railings must be installed in accordance with Ontario Building code
• If the grading plan is not part of a site plan or plan of subdivision show the connections to municipal services

Final Grading:

• All requirements listed above for Phase 1 and Revised Phase one
• Final grading checklist

Approval Processes:

1. Phase 1:
   • A Phase 1 grading plan will be approved if it complies with the design criteria described above.
2. Revised Phase 1:
   • In the event that gradients on the accepted Phase 1 grading plan cannot be met, a revised Phase 1 plan shall be submitted by a P. Eng. or equivalent for acceptance by the City prior to any final grading being completed on site.
   • The Revised Phase 1 grading plan will be approved if it complies with the design criteria described above.
   • In the event that the owner/builder submits revised gradients as part of the Final grading Plan without having prior acceptance approval, the final grading may not be accepted as constructed if the conditions of this document are not met.
   • The Master Grading Plan shall be revised by a P.Eng to correspond with the revised Phase 1 grading plan.
3. Final Grading:
   • A final grading plan may be accepted by the City, once it is approved by a Lot grading Professional providing compliance with the design criteria listed in this document and providing there are no adverse drainage conditions present. The Final Grading plan shall be submitted with the completed Final Grading Checklist.
   • Prior to final landscaping, ensure surveyed final elevations are provided at all proposed elevation locations, and any new break points
   • Final grading surveys and checks are to be completed once final landscaping is complete, elevations shall be taken after the placement of topsoil, prior to seeding, and after final sodding
   • Following final landscaping, ensure surveyed final elevations are provided at all proposed elevation locations, elevations are to be within a tolerance of 50 mm and providing minimum gradients are being met
   • Provide final gradient slopes to demonstrate minimum gradients are being met
   • In the event that minimum gradient tolerances are not being met, the final plan shall not be approved without an explanation
   • There is no tolerance for acceptance should the minimum depth of swales be less than specified; The swales shall be field measured for compliance
   • In the event the Final Revised Grading plan differs from the Master Grading Plan, the Master Grading Plan shall be revised by the Engineer to reflect the changes prior to acceptance
   • City staff are not able to properly complete Final Grading inspections during months when there is snow present on the ground

Fees

Fees are subject to the annual City of Brockville User Fee Schedule.

Should you have any questions with respect to the information provided, please contact the Supervisor of Engineering.