Clarington stretches from the Lake Ontario shore through Bowmanville, Courtice and Newcastle up onto the Oak Ridges Moraine, and its hydrogeological questions change along the way: dewatering and sewer discharge near the lake, shallow municipal wells in Orono, and moraine and farm water issues in the north. Wherever pumped water reaches Regional sewers, a hydrogeological study in Clarington also has to meet Durham Region's sewer rules.
What this means for your project in Clarington
- Studies here support subdivisions and buildings in the lakeshore communities, rural lots and farms on private wells, and site alteration and fill projects.
- The Municipality reviews planning applications and site alteration permits; Durham Region controls discharges to its sewers and supplies water; Central Lake Ontario or Ganaraska Region Conservation Authority reviews natural features.
- Groundwater can only go to a Durham sanitary sewer with written authorization, and dewatering must follow the provincial OPSS 518 specification.
- The local factor most likely to affect scope and cost: where the property sits. On the moraine, provincial plan policies add water budget and hydrological work; near Orono's shallow wells, source protection screening matters.
Clarington groundwater data
Calculated from public provincial datasets for Municipality of Clarington. Each value names its source; links are under Sources at the end of the page.
| Median depth of wells with a water level | 22.9 m (5,247 records reporting depth and water level) |
|---|---|
| Median static water level | 6.1 m below ground (5,247 records reporting depth and water level) |
| Records reaching bedrock | 13.8% of all records with a depth |
| Well records | 8,793 records (all types) |
| Active Permits to Take Water | 34 permits; largest purpose categories: Farm uses 18 (15 + 3), Commercial 4, Dewatering Construction 3 |
| Active construction and dewatering permits | 6 of 34 active Permits to Take Water |
| Conservation authority | Central Lake Ontario Conservation (49% of area); Ganaraska Region Conservation Authority (48% of area); Kawartha Conservation (1.9% of area) |
| Provincial plan areas | Oak Ridges Moraine 29%; Greenbelt 81.7% of area |
| Sewer discharge | Groundwater to Durham sanitary sewers only with written authorization (By-law 55-2013, s. 9); dewatering to OPSS 518 (s. 42) (Region of Durham) |
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.
Farming is the largest group of Clarington's water permits: 18 of the 34 active Permits to Take Water are agricultural, and 6 are for construction or dewatering. The well records show a median depth of wells with a water level of 22.9 m and a median static water level of 6.1 m below ground, and only 13.8% of records with a depth reach bedrock.
Durham Region's sewer use rules
The Region of Durham's Sewer Use By-law 55-2013 applies across Clarington's serviced areas, and three of its provisions shape any project that pumps groundwater:
| Provision | What it requires |
|---|---|
| Section 9 | No stormwater, groundwater, foundation drainage, non-contact cooling water or uncontaminated water to a sanitary sewer or land drainage connection to it, unless the Commissioner expressly authorizes it in writing |
| Storm sewer limits (Table 2) | Discharges to storm sewers must not exceed the limits for storm sewer discharge |
| Section 42 | All construction sites must comply with OPSS 518, the provincial specification for control of water from dewatering operations |
In practice, a building with a foundation drain or a construction site that dewaters plans for the storm sewer, with water quality tested against Table 2, and treats sanitary discharge as an exception that needs written approval. The hydrogeological study's flow estimate and sampling are what make either route possible.
Wells and lake water
Durham Region supplies Clarington's serviced communities from two very different sources. Newcastle and Newtonville are served, according to the Region's 2025 Newcastle report, from a water supply plant drawing Lake Ontario water through an intake about 1,070 m offshore. Orono, by contrast, relies on municipal wells, according to the Region's 2025 Orono report: two in service, each drilled to 13.7 m, with a third out of service. Shallow wells like these draw on groundwater close to the surface, so activities nearby, such as fuel or chemical storage, septic systems and road salt, are exactly what source protection screening looks at. In 2025 the Region reported sodium results of 26.3 mg/L and 42.6 mg/L from the two Orono wells, reported them as adverse results, and resampled with results meeting the drinking water standards.
Orono's wellhead protection area
Orono's wells sit in the Ganaraska Region Source Protection Area, one of six municipal residential systems there and one of 53 in the Trent Conservation Coalition Source Protection Region. The source protection fact sheet describes the aquifer as overburden covered by a deposit of relatively low hydraulic conductivity, serving about 1,793 people, and notes that the Ganaraska Source Protection Plan has applied since January 1, 2015. Policies apply only to significant drinking water threats, and in the Orono wellhead protection area the existing significant threats include agricultural activities. Waste, septic systems, livestock, pesticides, fertilizers, fuel, snow storage and other chemicals are the threat types the plan addresses.
For a farm, business or new building near the village, the study should establish whether the property is inside the wellhead protection area and, if so, which zone and vulnerability score apply, before planning fuel storage, manure handling or a septic system. Elsewhere in Clarington, Central Lake Ontario Conservation's area falls under the CTC Source Protection Plan instead.
The moraine and site alteration
About 29% of Clarington is in the Oak Ridges Moraine planning area, where the Oak Ridges Moraine Conservation Plan (O. Reg. 140/02) requires a hydrological evaluation near key hydrologic features and a water budget for some major development. Separately, Clarington's Site Alteration By-law 2024-017 requires a permit for placing or removing fill and changing grades, and bars importing fill from outside the Municipality; its development and agricultural instructions also flag the provincial excess soil registry for receiving sites taking more than 10,000 m³.
Questions to settle before scoping
- Which conservation authority and source protection plan cover the property: Central Lake Ontario under the CTC plan, or Ganaraska under the Trent plan.
- Whether the site is on the Oak Ridges Moraine or near a key hydrologic feature.
- Whether it lies in Orono's wellhead protection area, and which zone.
- For a serviced site, where dewatering water will go, since sanitary discharge needs the Region's written authorization.
Hydrogeological study cost in Clarington
| Study | Starting point | Full span |
|---|---|---|
| Hydrogeological report for a planning application | $12,000 – $18,000 | $12,000 – $150,000 |
| Rural lot severance study | $5,500 – $8,500 | $2,500 – $17,500 |
| Construction dewatering study | $9,000 – $14,000 | $9,000 – $62,500 |
| Pumping test for a water supply | $7,000 – $11,000 | $7,000 – $86,500 |
| Pre- and post-development water balance | $3,000 – $5,000 | $3,000 – $14,000 |
These are indicative ranges based on typical scopes, the same province-wide ranges the estimator uses, not prices specific to Clarington. Locally, the work is reviewed by the Municipality of Clarington, Durham Region and Central Lake Ontario or Ganaraska Region Conservation and, for water takings, the ministry, and the scope they ask for is what moves a quote. Dewatering projects need Durham's written authorization for sanitary discharge, and moraine sites can add water budget work. Excludes well drilling, government application fees and HST. Worked scenarios are in the cost guide for Ontario studies.
Projects that need a hydrogeological study in Clarington
- Lakeshore subdivisions and buildings. Dewatering to OPSS 518, storm sewer discharge testing and a long-term drainage design.
- Rural lots and farms. D-5-4 and D-5-5 work, and pumping tests for agricultural water takings.
- Moraine properties. Hydrological evaluation and water budget where the Oak Ridges Moraine plan applies.
- Fill and regrading. Site alteration permits, and excess soil registration for large receiving sites.
Working with a hydrogeologist in Clarington
Pumped groundwater in Clarington often heads for Durham Region's sewers, and the Region's sewer use by-law allows groundwater into its sanitary sewers only with written authorization, with dewatering following the provincial OPSS 518 specification. Build that into the schedule alongside the provincial EASR registration or permit. Near Orono, the shallow municipal wells bring source protection screening for some activities, and on the moraine provincial plan policies can add water budget work. Send the consultant the site location first so the hydrogeological assessment in Clarington is scoped to the right setting. The PGO public register confirms whether the geoscientist on a Clarington proposal is practising.
For a rural severance in Clarington, our article on whether a rural severance needs a hydrogeological study covers the lot size and servicing questions first.
Clarington questions
Can construction dewatering water go to a Durham sanitary sewer?
Only with written authorization: section 9 of the Region of Durham's Sewer Use By-law 55-2013 prohibits discharging groundwater, stormwater, foundation drainage or uncontaminated water to a sanitary sewer unless the Commissioner expressly authorizes it in writing. Storm sewer discharges must meet the by-law's Table 2 limits.
Is there a standard for how dewatering is done on Durham construction sites?
Yes: section 42 of the Durham by-law requires all construction sites in the Region to comply with OPSS 518, the provincial construction specification for control of water from dewatering operations, as amended.
Where does Orono's water come from?
From shallow wells: the Region's 2025 Orono report says the village has three municipal wells, with Well 5 out of service, and that Wells 3 and 4, each drilled to 13.7 m, supply the system, with an approved combined capacity of 1,745 m³/day.
Do I need a permit to bring fill onto my Clarington property?
Yes: Clarington's Site Alteration By-law 2024-017 requires a permit before you place or dump fill or topsoil, remove soil or alter grades, and no fill may be imported from outside Clarington. The Municipality publishes separate instructions for residential, agricultural and development applications.
How much of Clarington is on the Oak Ridges Moraine?
About 29% of the municipality is in the Oak Ridges Moraine planning area in the provincial boundary data, and 81.7% is inside the Greenbelt outer boundary. On the moraine, development near key hydrologic features needs a hydrological evaluation; our Caledon page explains the rules.
Which conservation authority reviews Clarington applications?
Mostly one of two: Central Lake Ontario Conservation (about 49% of the area in the provincial boundary data) or Ganaraska Region Conservation Authority (about 48%), with a small area under Kawartha Conservation.
Studies for Clarington properties
- Development Hydrogeological Study
Groundwater assessments that support subdivision, site plan and zoning applications.
- Severance Hydrogeological Study (D-5-4 / D-5-5)
Groundwater quality and well supply assessments for rural lot creation under MECP guidelines D-5-4 and D-5-5.
- Construction Dewatering Assessment
Groundwater inflow estimates and dewatering rates for excavations, basements and servicing trenches.
- Water Supply Well Assessment & Pumping Tests
Pumping tests, well yield and interference assessments for commercial, agricultural and communal supplies.
- Hydrogeological study cost guide
Ranges for every study type, side by side.
Near Clarington
Sources
- Sewer Use By-law 55-2013 (opens in a new tab), Region of Durham.
- 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.
- 2025 Newcastle Drinking Water System annual report (opens in a new tab), Region of Durham.
- 2025 Orono Drinking Water System annual report (opens in a new tab), Region of Durham.
- Orono Municipal Drinking Water System fact sheet (Ganaraska Region Source Protection Area) (opens in a new tab), Trent Conservation Coalition Source Protection Region.
- O. Reg. 140/02: Oak Ridges Moraine Conservation Plan (opens in a new tab), Government of Ontario (e-Laws).
- Site Alteration (Grading and Drainage), Site Alteration By-law 2024-017 (opens in a new tab), Municipality of Clarington.
- 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.