ARROWSMITH LAKE at partial capacity, as seen from the top of the Arrowsmith Dam. The Dam is operated and maintained by the Arrowsmith Water Service.

In 1996, The Regional District of Nanaimo, the City of Parksville and the Town of Qualicum Beach entered into a joint venture agreement to construct, operate and maintain the Arrowsmith Dam and associated water facilities. They formed the Arrowsmith Water Service (AWS) and received licence No. 110050 from the provincial government to extract water from the Englishman River.

The agreement of ownership and operating costs for the AWS partnership is as follows:

City of Parksville 63.9%
Regional District of Nanaimo 22.4%
Town of Qualicum Beach 13.7%

The dam was built to provide storage for a bulk water supply system to service Qualicum Beach, Parksville, and RDN water service areas in Nanoose Bay and French Creek. Construction was completed in October 1998 and the AWS partnership held an official opening ceremony on September 7, 2000.

Using City of Parksville forces, the AWS operates and maintains the dam and storage reservoir, which currently benefit the City of Parksville and the RDN Nanoose Bay Peninsula water system. Other RDN service areas will benefit as future components of the bulk water infrastructure are developed.

The Arrowsmith Dam controls the release of water from the Arrowsmith Lake reservoir to the Englishman River. The reservoir fills over the winter and spring and when full, it overflows to the river or is released through a piped discharge line under the dam.

The water licence requires AWS to release water from the reservoir between (approximately) June 1st and October 31st. The requirements for release of water may be amended through the Provisional Operation Rule (POR) attached to the licence. Over the summer and fall, the reservoir is drained to support river flows for domestic water extraction and fishery resources and is typically, by design, empty by the end of October.

Englishman River best source for supply

WHEN THE ARROWSMITH lake reservoir is full, it overflows the dam spillway to the Englishman River.

In the AWS service area, about 85 per cent of all drinking water comes from wells, and well capacity has declined in a number of areas. The Arrowsmith Dam is required to address uncertainty regarding the sustainability of groundwater supplies for present and future needs.

In 1989 the City of Parksville, the Town of Qualicum Beach and the Regional District of Nanaimo conducted independent water feasibility studies. Subsequent assessments of water quality and quantity, the environment, and system management and costs concluded that the best option for a supplementary water source was to dam Arrowsmith Lake.

The Englishman River water provided by the AWS is intended to supplement groundwater supply. Prior to project development, assessments confirmed that the Englishman River will be able to provide a long-term supplementary water supply for the AWS service areas. The current water licence held by AWS was based on providing sufficient supply to support water needs until 2021 (as outlined in the AWS water licence).