DOI: 10.25976/9h1b-ja71
title: Carvel Pitted Delta Lakes Survey

description: In the Carvel Pitted Delta, a post-glacial geological region west of Edmonton, Alberta, there are a large number of lakes that display a high diversity of morphology and water chemistry conditions. Some lakes are used extensively for recreation, others are surrounded by residential developments or agricultural land, while others have very little shoreline development due to being surrounded by large parcels of land. Some lakes have moderate levels of historical monitoring, but many have never been monitored. Beginning in 2019, upon learning about a few lakes with near-oligotrophic conditions, retired aquatic professional Dave Trew enlisted the support of the Alberta Lake Management Society and the University of Alberta to investigate a number of these lakes in the the summers of 2019 and 2020, as well as winter 2020-2021 (much of this data is available in the 'LakeKeepers Water Quality Data,' also available on Datastream). In the summer of 2021, the Mayatan Lake Management Association was enlisted to secure grant support from the Land Stewardship Centre, Stony Plain Fish and Game, and the North Saskatchewan Watershed Alliance to execute a survey of a high number of lakes within the region. 44 lakes were successfully sampled once each, where water chemistry measurements and samples were collected, along with preserved phytoplankton, zooplankton, and benthic invertebrate samples. In 2022, another survey was conducted and included 50 lakes, which were sampled following a slightly enhanced the sampling design. All water chemistry data is available in this dataset. Data analysis and reporting efforts for the survey are ongoing. Further data collection is probable. The primary goal of the project is to develop an updated and improved regional overview of lake water quality to support future land and water management decisions, and encourage location conservation and stewardship activities.
description: 2021: A single sample location was selected based on the historical "profile location," or the location used in past monitoring programs for surface to bottom depth measurements using a water quality probe. This location is generally the deepest location in the lake, and for lakes with no known historical profile location, the deepest location found was used as the sampling location. At this location, environmental observations were noted, then a YSI ProSolo was used to take temperature, dissolved oxygen and conductivity readings from surface to the bottom. A grab sample was taken at 0.5m, and was used for the analysis of a variety of water chemistry parameters, including majour nutrients and their fractions, chlorophyll-a, majour ions, and additional water quality parameters routinely reported on. Additionally, a near bottom grab sample, at approximately 1m off the bottom, was also collected and submitted for total phosphorus analysis. All water chemistry analysis was performed at Bureau Veritas, and chlorophyll-a analysis was performed at InnoTech. (Note, PL18 is a small pond, and no profile measurements or bottom grab samples were taken, and a single grab was taken from the shore). Data collection information reflects sampling of environmental observations and water chemistry parameters only, not the biological samples also collected.

2022: Profile sample site selection was the same as 2021, although some profile locations were moved if a deeper location was found. Profile measurements were the same as is 2021, with some lakes have light (PAR) profiles taken as well. A bottom sample was taken at each lake's profile location, approximately 2.5m from the bottom, to submit for total phosphorus analysis. All other laboratory analyzed water chemistry data came from an epilimnetic composite sampling approach, where three sites in total had vertically integrated samples collected from between 2 and 3m, and combined to represent a composite of each lake. Tubing with a one-way valve was used to collect vertically integrated samples. Shallow lakes were sampled following a composite of surface grab samples. Water quality parameters reported in 2022 are the same as 2021, with the exception of PAR. Biological samples also collected in 2022, including phytoplankton, zooplankton, invasive species and targeted sampling. Some lakes were sounded to collected bathymetric data.
description: Suspect values were verified with the analysis laboratory. Dissolved oxygen levels below 0 (eg. -0.1, -0.2), were adjusted to 0.