Wells Regulation – Completing the New Well’s Structure (technical bulletin)

This technical bulletin is one in a series of 11 on well issues created for a person who is considering a new water supply well or who currently owns a water supply well. The purpose of this technical bulletin is to summarize the information on the finishing steps of new well construction found in the Water Supply Wells Requirements and Best Management Practices manual published by the Ministry of the Environment and Climate Change. Additional information on new well construction is provided in the Wells Regulation New Construction of the Hole, Casing, Well Screen and Annular Space technical bulletin.

At the end of the construction of a new well, finishing steps must be conducted by the person constructing the well. This technical bulletin provides some of the finishing steps that must be completed to meet the requirements of Regulation 903 (Wells Regulation),as amended, made under the Ontario Water Resources Act.

Well development

Well development is a process that removes any drilling fluids or water introduced into the well during drilling. It also removes fine materials outside the well screen, minimizes the amount of sediment entering the well and improves well efficiency and flow of water into the well. Granular material (e.g., sand and silt) in the well water may damage the well owner’s pumping equipment, waterline and plumbing. The Wells Regulation requires the person constructing the well to remove debris such as well cuttings and drilling fluids from a new water supply well by developing (e.g. surging) the well until the well water is clear and free of sand.

Yield test

A well yield test provides important information about:

• The performance of the well as each well yields different quantities of water
• Some characteristics of the aquifer at the time that the well is tested

The person constructing the water supply well must conduct a well yield test before the well’s structural stage^{footnote 1[1]}is completed. Water levels and pumping rates must be recorded on the well record (see Chapter 10: Yield Test of the Water Supply Wells Requirements and Best Management Practices manual).

There is no minimum sustained pumping rate of water specified in the Wells Regulation for a residential water supply. The acceptable well yield should be determined by each well owner to meet his/her water needs. The yield test will provide an estimate of the sustained rate at which the well can be pumped.

Well owners should consult with municipalities and mortgage lenders (e.g. banks) to see if they require a minimum sustained pumping rate of water.

A Permit to Take Water under the Ontario Water Resources Act may be required if the yield test pumps at a rate that is greater than 50,000 litres per day (11,000 Imperial gallons per day).

Casing height and mounding

The Wells Regulation defines casing as pipe, tubing or other material installed in a well to support its sides, but does not include a well screen.

A sufficient height of casing above the ground surface, or above the floor of a well pit, helps to prevent the entry of surface water or foreign materials through the top of the well. In addition, ensuring that the surface drainage is such that water will not collect or pond in the vicinity of the well helps to reduce the potential for surface water to seep down the side of the well casing into the well.

The person constructing the well must meet the following casing height requirements upon completion of a new well’s structural stage.

Casing for a new well must extend at least 40 cm (16") above the highest point on the ground surface within a 3 m (10') radius from the outside of the casing after the ground surface is mounded to meet the surface drainage requirements.

The above requirement does not apply to a new jetted point or driven point well if the water supply well meets all of the following requirements:

• The well must be cased:
  • from the highest point on the ground surface within a 3 m (10') radius of the well’s casing after the ground surface meets the surface drainage requirements, as measured on completion of the well’s structural stage,
  • to the water producing zone, if the well obtains water from the overburden or to the bedrock if the well obtains water from the bedrock.
• The top of the casing must be a sufficient height above the ground surface to permit the attachment of a well tag.
• A permanent marker must be installed to identify the location of the well and be visible at all times of the year.

Well caps, covers and securing the well

Securing the well includes ensuring that the well cap, seal or cover is on properly and may include the use of a protective cover with locking cap, barriers or fences. The requirements for covering the well are as follows:

Dug or bored wells

The top of the casing of a well that is constructed by digging or boring must be covered with a solid, watertight well cover, so that surface water and other foreign materials cannot enter into the well.

Drilled or other wells

The top of the casing of a well that is not constructed by digging or boring must be sealed with a commercially manufactured vermin-proof well cap. An adequate vermin-proof well cap includes a properly installed and sealed commercially manufactured sanitary well seal on a drilled well and a commercially manufactured watertight and airtight well cap on a driven or jetted point well.

Exceptions to well cap or cover requirements

The cover, cap or seal is not required if all of the following criteria are met:

• A floor has been constructed around or adjacent to the casing of the well,
• The casing of the well is extended to at least 15 cm (6") above the floor that has been constructed around or adjacent to the casing of the well,
• A pump, including associated pump equipment such as a waterline, is installed above or adjacent to the well, and
• The top of the casing is shielded in a manner sufficient to prevent the entry of any material that may impair the quality of the water in the well.

Venting

When constructing a new water supply well, the well must be vented to the outside atmosphere so that all gases will safely disperse from the well unless the casing is used to transmit water out of the well. Some examples where casing is used to transmit water out of a well include flowing wells and driven point wells. Other venting requirements may be necessary when pumping equipment is installed in the well. Further information on venting is found in the Wells Regulation Installing Equipment in a Well technical bulletin.

Notifications

Mineralized water

Water containing in excess of 6,000 milligrams per litre (mg/L) total dissolved solids or 500 mg/L chlorides or 500 mg/L sulphates is considered to be mineralized.

Where a well is constructed and mineralized water is encountered, the person constructing the well must immediately notify the well purchaser and the owner of the land on which the well is located of the condition.

Natural gas or other gas

Where a well is constructed and natural gas is encountered, the person constructing the well must immediately notify the well purchaser, the owner of the land on which the well is located, and the Director under the Act of the condition.

The well owner must immediately take action if a water supply well produces mineralized water or produces gas. For further information on the appropriate action a well owner must take, see the Wells Regulation, the Wells Regulation Well Abandonment: When to Plug and Seal a Well technical bulletin and Chapter 14: Well Abandonment: When to Plug and Seal a Well of the Water Supply Wells Requirements and Best Management Practices manual.

Well tag (identification)

Well identification numbers link wells in the field with written records. Since October 2003, the Ministry of the Environment has issued steel well tags the size of a credit card to persons who construct wells in Ontario. Each tag has a unique number.

Before the structural stage of a new cased well is completed, the person constructing the well must obtain a well tag from the ministry and affix it permanently to the outside of the casing or to a permanent structure associated with the well.

In many cases, the requirement to affix a well tag to a well also applies when a water supply well is altered. See the technical bulletin Wells Regulation Well Repairs and Other Alterations for further information on tagging existing wells.

The affixed well tag must be visible and not hidden by the well cap, any other components of the well or equipment associated with the well.

The well tag is important as it links detailed information on the construction process and design of the well with the well in the field.

This information is crucial to persons who wish to:

• locate a well in the field,
• link a well record to a well,
• test and sample a well, and
• maintain, alter or abandon a well.

Information for the well purchaser

Unless the well purchaser otherwise directs, on the day that the structural stage is complete, other than for a minor alteration, the person constructing the well must:

• deliver an information package from the Ministry of the Environment to the well purchaser,
• provide a water sample, of at least one litre, to the well purchaser for visual examination, and
• measure the depth of the well in the presence of the well purchaser.

Further information on the term "minor alteration" of a well is found in the technical bulletin titled Wells Regulation Installing Equipment in a Well.

Well record

On completion of a well’s structural stage, other than for a minor alteration or the installation of a pump, the person constructing the well must complete a well record for the well following the instructions and explanations on the record, and:

• within 14 days, deliver a copy of the well record to the well purchaser and the owner of the land on which the well is situated,
• within 30 days, forward a copy of the well record to the Director under the Act, and
• retain a copy of the well record for at least two years.

Well records provide construction and general water quantity and quality information. The well tag is a unique identifier that links the well in the field with the well record. Well records and tags are a notification system for use by the province, consultants, contractors and well owners to:

• Provide information on the groundwater and geology of an area, including:
  • Groundwater availability
  • Depth to water
  • Possible flowing well conditions
  • Possible mineralization or gases
• Provide baseline information in case of spills
• Assess equipment needs and estimated costs of construction
• Help protect well owners and contractors from liability issues
• Provide information to manage the groundwater resources
• Provide information for consultants and regulators on groundwater quality and quantity issues in the area
• Assist in locating wells when purchasing a new property to ensure they are properly maintained or abandoned (plugged and sealed)

Test holes and dewatering wells

New test holes and dewatering wells, as defined by the Wells Regulation, have other well construction requirements and exemptions. For further information on the construction requirements for test holes and dewatering wells, see the Wells Regulation.

Additional information sources

This technical bulletin on well issues is one in a series of 11 created for owners of water supply wells which are available on the Water Supply wells: technical bulletin page.

Further information on well construction for water supply wells can be found in the related technical bulletin Wells Regulation Well Repairs and Other Alterations as well as in Chapter 5: Constructing and Casing the Well, Chapter 6: Annular Space & Sealing and Chapter 7: Completing the Well’s Structure of the Water Supply Wells Requirements and Best Management Practices manual.

A copy of the Water Supply Wells Requirements and Best Management Practices manual can be obtained from the ministry’s website.

A copy of the Ontario Water Resources Act, Regulation 903 as amended made under the Ontario Water Resources Act (Wells Regulation), and other regulations can be obtained from the e-Laws web site.

The publications are also available by calling the Publications Information Centre at 1-800-565-4923 or 416-325-4000.

For further information about wells, contact the Wells Help Desk at 1-888-396-WELL (9355) or the nearest Ministry of the Environment and Climate Change office listed in the blue pages of the telephone directory.

PIBS 7933e

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