Peterborough is a river city: its drinking water comes from the Otonabee River, not from wells, so source protection here is about what reaches the river upstream of the intake. Most hydrogeological studies in the city support construction and redevelopment, with groundwater levels, dewatering and the water quality of pumped water as the main questions. A hydrogeological study in Peterborough near the river can also bring in source protection screening.
What this means for your project in Peterborough
- Most studies support buildings with basements and servicing that may need construction dewatering, and redevelopment of former commercial or industrial land.
- The City asks for a hydrogeological assessment on every major development application, with a pre- to post-development water balance.
- Properties within about 120 m of the river near the intake fall in intake protection zones, where a Risk Management Official's notice is needed before an application is complete.
- The local factor most likely to affect scope and cost: whether the site is in IPZ-1 or IPZ-2, which brings in source protection screening and limits on new drains and excavation-related pathways.
Peterborough groundwater data
Calculated from public provincial datasets for City of Peterborough. Each value names its source; links are under Sources at the end of the page.
| Median depth of wells with a water level | 19.5 m (1,084 records reporting depth and water level) |
|---|---|
| Median static water level | 5.5 m below ground (1,084 records reporting depth and water level) |
| Records reaching bedrock | 20.4% of all records with a depth |
| Well records | 3,076 records (all types) |
| Active Permits to Take Water | 9 permits; largest purpose categories: Commercial 3, Remediation 2, Dewatering Construction 1 |
| Active construction and dewatering permits | 1 of 9 active Permits to Take Water |
| Conservation authority | Otonabee Conservation (100% of area) |
| Provincial plan areas | None in the Oak Ridges Moraine, Greenbelt or Niagara Escarpment Plan areas |
Source: Well Records (Water Well Information System), MECP (WWIS_2026a), retrieved 2026-10-14.
Source: Permit to Take Water, MECP (PermitsToTakeWater_26-01), retrieved 2026-10-14.
Source: Conservation Authority Administrative Area, Ontario GeoHub, retrieved 2026-10-14.
Source: Oak Ridges Moraine (ORM) Planning Area, Ontario GeoHub; Greenbelt Outer Boundary, Ontario GeoHub; Niagara Escarpment Plan Boundary, Ontario GeoHub; retrieved 2026-10-14.
Figures count records inside the municipal boundary that report a value; well locations and values are as submitted by well contractors, and MECP notes inaccuracies exist. How these figures are calculated.
With a river supply, Peterborough needs few large water takings: the provincial data lists just 9 active Permits to Take Water inside the city. Where well records exist, groundwater commonly stands 5.5 m down and only 20.4% of the holes with a depth reach bedrock.
What the City's Official Plan asks for
The City's Official Plan (approved April 2023, consolidated June 2024) puts its groundwater policies in section 6.1.4, Water Resources. The ones that most often decide whether a study is needed:
| Situation | What the plan says |
|---|---|
| Any major development application (6.1.4 f) | A hydrogeological assessment, including maintaining the pre- to post-development water balance and substantially maintaining infiltration, recharge and peak flows |
| Development or site alteration in an IPZ, wellhead protection area, recharge area or highly vulnerable aquifer (6.1.4 x) | A hydrogeological or impact assessment may be required, scoped by the City with the Conservation Authority; results can be secured through site plan control, a holding symbol or special zoning, and the City should not approve an application whose risk cannot be mitigated |
| New lots on a waterbody (6.1.4 g) | Development, including any septic tile bed, set back at least 30 m from the normal high water mark |
| Land in IPZ-1 or IPZ-2 (6.1.4 k) | Pre-consultation with the Risk Management Official and a section 59 notice for a complete application |
At pre-consultation the City sets the list of supporting studies. Section 7.21.2 names a hydrogeological assessment including a wellhead protection area plan and geotechnical study, a water balance analysis, and a hydrogeological and geotechnical study under servicing, so one investigation often feeds several of these reports.
The Otonabee River intake
The Trent Assessment Report sets out the intake details and the vulnerability of the zones around it. Otonabee Conservation's Peterborough page adds that the system is one of 12 municipal residential systems in the Otonabee-Peterborough Source Protection Area:
| Item | Detail |
|---|---|
| Source and population | Otonabee River; about 79,320 people served |
| Intake | Two 760 mm pipes about 2 m deep, 22 m from shore; a Type D intake on an impounded river |
| Average pumping | 37,852 m³/day |
| Vulnerability scores | IPZ-1: 10; IPZ-2: 9; IPZ-3a (river up to Lakefield): 6; IPZ-3b (tributaries including Sawyer Creek): 3 |
The report gives IPZ-2 the highest possible area factor because several transport pathways, including storm outfalls, lie close to the intake and the land upstream is urban. The Official Plan defines IPZ-1 and IPZ-2 to include the land within 120 m of the high water mark, so a riverside property can sit inside a zone even when the intake is some distance away.
New drains and pathways near the river
Under policy OT-2 of the Trent Source Protection Plan, a transport pathway is a human-made condition that lets contaminants reach the water supply faster. For a surface water intake the plan's examples are storm drainage infrastructure, such as sewers, culverts and ditches, and tile drains. In IPZ-1 the municipality should not approve a new one without a statement from a qualified person that it will not significantly increase the intake's vulnerability; in IPZ-2 scored 8 or more, it should consult the source protection authority and ask the proponent to show the supply is not endangered, with a condition to decommission unused wells under Regulation 903. The Official Plan goes further for IPZ-1: land uses that create transport pathways should not be permitted there at all (6.1.4 l).
Where pumped groundwater can go
Peterborough's By-law 15-075 controls sewer discharges. It prohibits sending water from any source other than the City's distribution system to a sanitary or combined sewer (s. 2.1.2), and allows foundation drain water from an existing sump into a sanitary or combined sewer only temporarily and under an agreement with the City. Storm sewer discharges must not impair the quality of any waters or breach a provincial approval (s. 3.1.1). It has no separate approval for construction dewatering, so the dewatering assessment should include water quality results and a proposed outlet the City can accept. New or reconstructed buildings cannot connect a private storm sewer to the sanitary sewer (s. 4.10.3).
What that means for a study in the city
Because the city does not drink groundwater, the wellhead protection issues that drive studies in places like Guelph or Kitchener do not apply in the same way. A study inside the intake protection zone instead needs to consider runoff and shallow groundwater moving toward the river, especially where fuel, chemicals, salt or a septic system are involved. Elsewhere, studies focus on construction: groundwater levels for foundations, dewatering estimates for the EASR or a Permit to Take Water, and water quality before discharge.
Hydrogeological study cost in Peterborough
| Study | Starting point | Full span |
|---|---|---|
| Excavation dewatering assessment | $9,000 – $14,000 | $9,000 – $62,500 |
| Development groundwater study | $12,000 – $18,000 | $12,000 – $150,000 |
| Water balance for a planning application | $3,000 – $5,000 | $3,000 – $14,000 |
| Wellhead protection risk assessment | $4,500 – $7,000 | $4,500 – $15,500 |
These are indicative ranges based on typical scopes, the same province-wide ranges the estimator uses, not prices specific to Peterborough. Locally, the work is reviewed by the City of Peterborough and Otonabee Conservation and, for water takings, the ministry, and the scope they ask for is what moves a quote. Sites in the intake protection zones add source protection steps, and major development needs a water balance. Excludes well drilling, government application fees and HST. The province-wide cost breakdown shows what each range includes.
Projects that need a hydrogeological study in Peterborough
- Buildings with basements and servicing. Groundwater levels, construction dewatering and a discharge plan the City can accept.
- Major development applications. A hydrogeological assessment with a pre- to post-development water balance.
- Riverside sites in IPZ-1 or IPZ-2. Risk Management Official pre-consultation, a section 59 notice and a qualified person's statement for new drainage.
- Redevelopment of former commercial or industrial land. Groundwater quality alongside the environmental site assessment.
Working with a hydrogeologist in Peterborough
On land in Peterborough's intake protection zones 1 and 2, pre-consult the Risk Management Official at Otonabee Conservation before filing: the Official Plan makes a section 59 notice part of a complete application there. For major development anywhere in the city, expect the City to ask for a hydrogeological assessment in Peterborough with a pre- to post-development water balance. If construction will pump groundwater, settle the outlet with the City early, since its sewer by-law keeps it out of sanitary sewers and has no separate dewatering approval. A Peterborough proposal should name the P.Geo. responsible, which Professional Geoscientists Ontario's register confirms.
For the provincial registration that sits beside the City's sewer rules, see EASR dewatering registration, step by step.
Peterborough questions
Where does Peterborough's drinking water come from?
The Otonabee River: the Peterborough Utilities Commission's 2024 drinking water report describes the Otonabee River as a surface water supply treated as an unprotected source, so it always receives full treatment at the water treatment plant on Water Street North, which has a rated capacity of 104 ML/day.
My site is in the intake protection zone. What changes for a planning application?
Two things under section 6.1.4 k) of the Official Plan: you must pre-consult the Risk Management Official, and a notice under section 59(2) of the Clean Water Act from that official is required before the City treats an application in IPZ-1 or IPZ-2 as complete. Otonabee Conservation's Peterborough page lists the Risk Management Official's contact at Otonabee Conservation.
Can I pump construction groundwater into the sanitary sewer?
Generally not: section 2.1.2 of By-law 15-075 prohibits discharging to a sanitary or combined sewer water that came from a source other than the City's water distribution system (stormwater aside), and to a sanitary sewer any stormwater or uncontaminated water. The by-law has no separate construction dewatering approval, so confirm the discharge route with the City before pumping starts.
Do excavations near the Otonabee River need anything extra?
They can: Peterborough's IPZ-1 scores 10 and IPZ-2 scores 9 in the Trent Assessment Report, so the Trent Source Protection Plan's transport pathway policy applies. Storm drains, culverts, ditches and tile drains are the examples it gives for surface water systems, and in IPZ-1 the City should not approve one without a qualified person's statement that it will not significantly increase the intake's vulnerability.
Which conservation authority reviews Peterborough applications?
Otonabee Region Conservation Authority, which covers the whole city in the provincial boundary data. Under section 6.1.4 x) of the Official Plan, the City sets the requirement and scope of a hydrogeological assessment in a vulnerable area in consultation with the Conservation Authority.
Studies for Peterborough sites
- Construction Dewatering Assessment
Groundwater inflow estimates and dewatering rates for excavations, basements and servicing trenches.
- Development Hydrogeological Study
Groundwater assessments that support subdivision, site plan and zoning applications.
- Water Balance Assessment
Pre- and post-development water budgets for planning approvals and low impact development design.
- Source Water Protection Risk Assessment
Assessments for activities proposed inside wellhead protection areas and other vulnerable areas.
- Hydrogeological study cost guide
Ranges for every study type, side by side.
Near Peterborough
Sources
- Well Records: Water Well Information System (WWIS_2026a) and county Well Record Data Reports (WW_Reports_2026a) (opens in a new tab), Government of Ontario (MECP), Ontario Data Catalogue.
- Permit to Take Water dataset (PermitsToTakeWater_26-01) (opens in a new tab), Government of Ontario (MECP), Ontario Data Catalogue.
- Conservation Authority Administrative Area (opens in a new tab), Ontario GeoHub.
- Oak Ridges Moraine (ORM) Planning Area (opens in a new tab), Ontario GeoHub.
- Greenbelt Outer Boundary (opens in a new tab), Ontario GeoHub.
- Niagara Escarpment Plan Boundary (opens in a new tab), Ontario GeoHub.
- City of Peterborough Official Plan (consolidated June 2024), sections 6.1.4 and 7.21.2 (opens in a new tab), City of Peterborough.
- Trent Assessment Report (October 2026), chapter 4: surface water intakes (opens in a new tab), Trent Conservation Coalition Source Protection Region.
- Peterborough municipal drinking water system (intake protection zone and threats) (opens in a new tab), Otonabee Conservation (Otonabee-Peterborough Source Protection Authority).
- Trent Source Protection Plan (updated October 8, 2026), policies G-9 and OT-2 (opens in a new tab), Trent Conservation Coalition Source Protection Region.
- R.R.O. 1990, Reg. 903: Wells (consolidated to e-Laws currency date October 12, 2026), sections 1, 1.0.2, 1.1 and 21 (opens in a new tab), Government of Ontario (e-Laws).
- By-law 15-075: discharge of sewage and land drainage (opens in a new tab), City of Peterborough.
- Public Register (registered members) (opens in a new tab), Professional Geoscientists Ontario.
- Municipal Boundary - Lower and Single Tier (opens in a new tab), Ontario GeoHub.
- OHN Waterbody, 2M generalized layer (provincial hydrography dataset) (opens in a new tab), Ontario GeoHub.
- 2024 Annual Report on Drinking Water Quality, Peterborough Water Treatment System (opens in a new tab), Peterborough Utilities Commission (City of Peterborough).
- O. Reg. 63/16: Registrations under Part II.2 of the Act - Water Taking (consolidated to e-Laws currency date October 9, 2026) (opens in a new tab), Government of Ontario (e-Laws).