Halifax Water requires all persons to have appropriate permission prior to using any Halifax Water infrastructure. For the average person this means having an account with Halifax Water and paying your regular bill. For construction sites, and other non-permanent discharges, this means obtaining a Dewatering Approval from Halifax Water.
No excavation or trench water is approved to be dewatered into Halifax Water’s systems without prior approval. If you are working on a project that may require dewatering you are encouraged to apply ahead of time as the approval time may be a couple weeks depending on your site history. Some sites may not be approved to dewater due to their history, for example a contaminated site.
- Representative water quality testing will always be required before dewatering.
- Dewatering must meet all the conditions set out in Section 63 of Halifax Water’s Regulations, including the concentration limits listed in Table 6.
- Dewatering of construction water to the stormwater system is not approved.
- No dewatering will be approved during or immediately after rain events.
- All sites will be required to have pretreatment for TSS, pH, and other site-specific parameters.
- If site conditions change, the approval stipulations will be updated accordingly.
- Halifax Water reserves the right to prohibit any dewatering to any of its systems.
Additional requirements for sites with history of contamination
- Dewatering from non-remediated contaminated sites and sites with no closure report will not be approved to Halifax Water's systems.
- Dewatering from remediated sites with a closure report will reviewed on a case by case basis.
- Any dewatering that is approved will require pretreatment and additional conditions.
- An Environmental Site Professional with experience in contaminated water treatment will be required for pretreatment design and sampling.
- Pretreatment may include carbon cells, flocculation, filtration, commercial treatment systems, and other acceptable treatment methods.
Example Approval Conditions
Approval conditions will be customized to your site. Failure to follow all the conditions found in your letter will be terminated if the requirements are not met.
- Dewatering is only approved in the approved manhole or lateral.
- No dewatering is approved during any precipitation event.
- No dewatering is approved within 12 hours after a precipitation event.
- Over 25mm of precipitation will require Halifax Water approval to resume dewatering.
- Dewatering may be restricted between specific hours.
- Dewatering shall not cause any flooding of nearby properties, ice accumulation or erosion.
- Maximum specified pump rates must not be exceeded.
- The pump must be elevated on a clear stone pad, floating, or placed in a location where it will not intake mud, debris, or other solids.
- Pumps are to be always attended while operating, including overnight hours.
- All dewatering to the wastewater system is subject to the most current volumetric wastewater fee in the Halifax Water Regulations.
- Invoicing will be monthly.
- The approved method of calculating flow will be specified in the approval letter.
- Flow meter: a flow meter must be placed on the pump discharge.
- Batch Flow: the number of batches and the size of the tank will determine the fees.
- Applicants will be required to pay for any Halifax Water audit samples taken.
- Additional cost recovery may apply as listed in Section 31 of the Halifax Water Regulations.
- Any required pretreatment system must be in place during dewatering and always maintained.
- Changes to the pretreatment system may be required at any time during the dewatering process as site conditions change.
- In the event the pretreatment system fails, dewatering must stop immediately.
- Dewatering must be in completed in accordance with the limits outlined in Table 6 in the Halifax Water Regulations.
- Ongoing testing of site-specific parameters will be required. For example, daily TSS, BTEX, and pH sampling.
- Perform daily checks for visible sheen and odour, keep written records.
Halifax Water has a log sheet that can be used to track dewatering during the length of the approval. Log sheets can be sent in on a monthly basis to be processed for invoicing.
If you have any questions on the process or about the status of your application, please email P2@halifaxwater.ca.
