Central Alberta Fly Tying Club: AERATION UPDATE

Wednesday, March 2, 2016

AERATION UPDATE – MARCH 1, 2016

Despite our best efforts and a significant amount of time and energy put into the project by ACA staff, our aeration program for 2015/16 has not produced the results we were hoping for. As stated previously, because of criminal liability issues associated with Sec 263 of the Criminal Code, we changed our aeration program this winter from the usual surface aeration to a sub-surface diffuser system. We hoped that by using the sub-surface diffuser system, we would be able to continue to provide enough dissolved oxygen (DO) into the water column to maintain fish over the winter, while at the same time containing the opening in the ice created by the aeration, through the installation of a dock and chain-link system.

Our original plan was to aerate only a portion of the lakes this winter to test the sub-surface diffuser system; however, at the request of the Minister of Environment and Parks, we proceeded with the implementation of aeration systems at all the lakes we would normally aerate. Fortunately, Alberta Environment and Parks was able to take over aeration using surface aerators at two locations, along with two municipal governments and one private individual. You will note in the table below, with the participation of these groups, five of the fifteen lakes that ACA would normally aerate over winter were aerated using surface aeration.

Unfortunately, we experienced more difficulties with the sub-surface diffusers than we had expected. Containing the hole created in the ice within the dock system proved to be a difficult task, particularly with the warm winter conditions we experienced this year. As a result, in many instances we were forced to reduce the amount of air being pumped by the diffusers into the water column. While this change allowed for the hole to be contained, it appears in most cases it reduced the amount of oxygen entering into the water column to the point at which the aeration was ineffective at maintaining adequate DO levels.

We are currently working with Alberta Environment and Parks to resolve the aeration issue to ensure that surface aeration can be re-implemented at all lakes in 2016/17.

The table below provides an update as to the aeration system and effectiveness at each lake as of March 1, 2016.

NAME	AERATION SYSTEM	COMMENTS
NORTHWEST REGION
Cecil Thompson Pond	MD surface aeration	DO level good. Good potential for fish to survive.
East Dollar Lake	ACA diffuser	DO low. Limited potential for fish survival. Dead trout have been observed.
Figure Eight Lake	AEP surface aeration	DO level good. Good potential for fish to survive.
Spring Lake (Grande Prairie)	Fall aeration only	This lake is normally only aerated in the fall. DO level good. Good potential for fish to survive.
Sulphur Lake	AEP surface aeration	DO level good. Good potential for fish to survive.
Swan Lake (Grande Prairie)	County surface aeration	DO level good. Good potential for fish to survive.
CENTRAL REGION
Beaver Lake	diffusers shutdown Feb 5	DO becoming a concern. Potential for some fish loss.
Birch Lake	No aeration	DO still ok. Good potential for fish survival.
Fiesta Lake	diffusers shutdown Jan 28	DO low. Limited potential for fish survival. Dead minnows have been observed.
Hansen Reservoir	No aeration	Low DO levels prior to equipment being installed as a result aeration was not initiated. Limited potential for fish survival.
Ironside Pond	Diffusers shutdown Feb 5	DO becoming a concern. Potential for some fish loss.
Mitchell Lake	Diffusers shutdown Jan 18	DO still ok. Good potential for fish survival.
Millers Lake	ACA diffuser	DO low. Limited potential for fish survival. Dead trout have been observed.
Muir Lake	ACA diffuser	DO becoming a concern. Potential for some fish loss.
Spring Lake (Stony Plain)	Private surface aeration	DO level good. Good potential for fish to survive.
SOUTH REGION
Coleman Fish and Game Pond	ACA diffuser	DO are a concern. Potential for fish loss.