Who is Extracting Sylvan Lake Watershed Groundwater?

The SLWSS monitors groundwater consumption. Much of that well-water withdrawal is eventually exported from the watershed’s surface and underground inventory as community wastewater. It is collected and processed by the Town of Sylvan Lake in its sewage lagoons. To help treated effluent on its way through Cygnet Lake to the Red Deer River, a comparable volume is pumped from Sylvan Lake itself to supplement Outlet Creek flow. In effect, every flush drops the lake level a tiny amount.

The Town of Sylvan Lake is the main licensed user of well water in the watershed. The municipal system annually delivers about 1.5 million cubic metres of water for domestic, business and other purposes. Water wells registered to the Town of Sylvan Lake are shown as yellow dots in this map that was acquired from the Alberta water well database:

Summer Villages, other lakefront settlements, farm and ranch and industrial users outside the TSL rely on groundwater supplies for domestic needs too. Many of the domestic, agricultural and industrial water wells are shown in this map that includes the Sylvan Lake watershed:

 

 

 

The Sylvan Lake Groundwater Situation in Perspective and Pictures

The Sylvan Lake watershed and its supply of groundwater are dependent on a fine balance between incoming and outgoing water. The net amount is absorbed and stored underground by the soil and becomes available for domestic and agricultural use. The following ERCB/AGS maps included in this post show how the natural system and its regional water balance works.

The Sylvan Lake watershed and the lake occupy a small part of that area and are located about 20 km west of Red Deer. See the lake aligned in a NW direction in this series of maps. Zoom in if you are viewing the images on a phone. Check the legends for the colour-coded values.

Ave Ann Total Precip-Fig4.2-ECC
Central Alberta is relatively dry region and typically receives 500 mm of precipitation annually. The graphic above shows that the foothills to the west receive slightly more rain and snowfall than does the central corridor.
Ave Act EvapoTrans-Fig4.4-ECC
About 60% of the incoming precipitation sublimes or evaporates from snow, ice, wetlands and lake surfaces and by transpiration from crops and forested areas. This maps shows that watershed loses about 300 mm of water by those processes.
Ave Ann Act Runoff-Fig4.7-ECC
The typical annual surface runoff is less than 45 mm.

Continue reading “The Sylvan Lake Groundwater Situation in Perspective and Pictures”

What Happens Under Sylvan Lake Ice in Winter?

In all our monitoring programs we focus on Sylvan Lake water quality , yet the records show that those data don’t change very fast. In comparison, lake water temperature (T) does cycle dramatically as it can vary from near zero Celsius (C) under the ice and 4 C above the sediment in the winter, to as high as 23 C in a very warm summer. Those Ts and their rates of change must have an impact on the chemical and biological process: on the aquatic populations, the food chain, and on the general health of the lake.

Let’s walk through an annual cycle starting in a fall season. First, cold fall and winter weather removes heat from the surface layer. As the density of liquid water increases when it is cooled, the colder, denser, surface water sinks, mixes, and gradually lowers the T of the whole water column. Water reaches a maximum density at 4 degrees C, so the deeper areas of the lake never freeze right to the bottom. Eventually an ice layer forms on the surface and seals the surface of the lake from the atmosphere. The density and T gradients stabilize the water column as this first Alberta Environment graph of T measurements at different depths at the deep-water sampling station shows:

In the January-March period in the listed years between 1984 and 2002 the lake water at the 10 metre depth cooled to between about 1.2 and 3.3 C. Under the ice at 1 m depth the recorded Ts were between 0 and 2 C. Right at the bottom of the lake at the 16 metre depth, Ts reached about 4 C where water reaches its maximum density. At that point, both warmer or colder volumes of water will be more buoyant and will rise, mix, exchange heat, and equilibrate at a new level in the water column. That density-driven mixing makes the lake a dynamic place.

The fall and winter T conditions that caused the lowest vertical T gradient in 1984 and the highest one in 1999 are illustrated in these two graphs acquired from the Alberta Agriculture weather archives:

Temperatures in Fall 1983 and Winter 1984

Temperatures in Fall 1998 and Winter 1999

A simple explanation for the difference between the two lake T profiles is difficult to see however early rapid heat removal in 1984 by the very low November minimum Ts may have been the primary cause. In contrast, the 1998 fall season was relatively warm.

That is quite a difference in refrigeration. Cooling the 420 million cubic metres of Sylvan Lake water by an extra 2 C required removal of 3740 Terajoules of thermal energy!

Continue reading “What Happens Under Sylvan Lake Ice in Winter?”

Is There Evidence for Climate Change in the Sylvan Lake Watershed?

In his book “Landscapes and Cycles” Jim Steele, an authority on the ecosystems of the Sierra Nevada in California, makes a simple and obvious point about climate change: local climate variables, not global ones, drive locally observable climate change.

So, what do we know about those variables and the response of the Sylvan Lake watershed? Here are a few graphics that summarize facts from the official sources of weather and climate records:

Temperature

Daily mean, maximum and minimum temperatures recorded at the Red Deer Airport are certified by Environment Canada.

 

Mean Temp 1994-2014

T Max-Min 1994-2014

Precipitation

Rain and snow are recorded as daily precipitation. This graph displays 20 years of accumulated precipitation measured at the Red Deer Airport. The slope is highly linear over the period with seasonal differences causing the annual fluctuations in rate.

Cum Precip 1994-2014

Interpolation of data from the Alberta Agriculture Hespero and other regional weather stations around Sylvan Lake, for six townships in which the watershed is located, shows that the annual rate of precipitation has remained constant since 1961. A climate change impact on precipitation is not significant.

50 Years of Precipitation

Continue reading “Is There Evidence for Climate Change in the Sylvan Lake Watershed?”

SLWSS Comments for the Public Hearing on the Amendment of the Birchcliff Land Use Bylaw #199/17

The Summer Village of Birchcliff has invited public comment on its review of several clauses of its land use bylaw that control the size of structures and impermeable surfaces on private property. The SLWSS provided the following  recommendations on the specific and more general aspects of land use regulation on October 13:

Continue reading “SLWSS Comments for the Public Hearing on the Amendment of the Birchcliff Land Use Bylaw #199/17”

Three Decades of Sylvan Lake Water Quality Data

Alberta Environment and Parks archives historical water quality data for Sylvan Lake.

Click on this link for a pdf file of the composition of the lake water downloaded in October 2017.

Water Quality Data-Sylvan Lake- 2017-10

The N-P-K plant nutrient, chlorophyll, and Secchi disk data track the natural variability of Sylvan Lake.

As Sylvan Lake is a bathtub-like water body, some components like the conserved indicator ions sodium and chloride have become more concentrated over time as surface and groundwater, and fallout from the air, carry soluble substances into the lake, and evaporation removes water during the open water season

The effect of the watershed human population on lake water quality is demonstrated by the increasing concentrations of some ions that are introduced from diffuse contaminant sources such a winter road salting. As expected, the lab-measured specific conductance has increased slowly as the salinity of the lake has risen.

Sampling campaigns completed during the last two decades have been facilitated by Sylvan Lake Watershed Stewardship Society volunteers in partnership with the Alberta Lake Management Society field technicians. Partial funding in recent years was provided by the Sylvan Lake Management Committee, the RDRWA and Alberta Environment and Parks. The total cost of a May-to-October 5-day campaign is close to $10,000. Water quality monitoring is not free.

The President’s Annual Report for 2017

State of the Watershed Update

Two summary reports compiled by the Alberta Lake Management Society included Sylvan Lake water quality data collected during our 2016 campaign. Because of the low nutrient concentrations, which are  indicators of the potential for blooms of nuisance algae, Sylvan Lake is now ranked as oligotrophic, the lowest category of lake productivity. As phyto- and zoo-plankton are a critical part of the lake’s food chain we will now watch the condition of aquatic life more closely.

The boundary of the Sylvan Lake watershed as defined by Alberta Environment and Parks was acquired from the Alberta Lake Management Society in GIS file format. It is compared to other reference perimeters in this Google Earth Pro image. Watershed municipalities have not agreed on a legal boundary.

The SLWSS Cumulative Effects database is updated to include the most recent data reported by Alberta Municipal Affairs. The information is posted as a set of graphics without commentary. Apart from growth in the Town of Sylvan Lake, most variables remain stable. Data are converted to parameters/hectare to facilitate projections of the characteristics of a future more densely populated watershed.

Runoff, Precipitation and Water Balance in 2017

 Spring runoff is recorded in this music video of Golf Course Creek peak flow. It is usually an important event for transferring sediment and mobile soil constituents off the land into the lake, however this year’s version did not last long. Cumulative precipitation in 2017 measured at the Alberta Agriculture Hespero weather station is about 0.1 metre below the long term average. The 2017 level of Sylvan Lake dropped about 0.2 metres after July1 from lack of precipitation and water diversion by the Town of Sylvan Lake. Those observations mean that the water balance of the watershed is close to the historic norm.

That is so even with the AEP-regulated emergency practice of pumping crown-owned water from Sylvan Lake to carry treated sewage lagoon effluent through Cygnet Lake and into the Red Deer River. The impact of pumping on the lake volume is small, less than 0.4%, and comparable to the rate of withdrawal caused by natural evaporation rate that typically occurs after July 1.

Monitoring Land Use Changes

We monitor changes in land use with special attention to the Sylvan Lake shoreline. We converted video from the SRD  2007 helicopter survey to a streamable format that can now be viewed easily even on a smartphone. We considered commissioning a new drone survey, however high resolution Google Earth imagery is available for free. We confirm and document those aerial and satellite observations with ground and lake-level investigations to update risk assessments. For example, here is the latest “Juno Beach” landscaping look and a surprising Blissful Beach slope failure.

The Flipside Project

Sometimes we even have fun. We ran a lake water sampling demonstration for elementary school kids at the Flipside after-school clubhouse and simulated an on-the-water campaign on a miniature scale.

 Best Stewardship Practices for Boaters

Lake stewardship among boaters seems to fall well down their “to-do” list. Nevertheless, the diligent SLWSS Quiet Enjoyment Initiative team led by Kent Lyle continues to work with the watershed municipalities to educate boaters with brochures and signs about the need for respectful noise abatement. Alberta Environment and Parks (AEP) has also urged boaters to Respect Our Lakes with new signage. Recreational lakes are receiving more AEP attention. The Society provided the Town of Sylvan Lake (TSL) with our opinion on subsidized boat launch access.

Risk to the Lake from the TSL West Area Development

On our watch list is the potential impact of the TSL’s new West Area Development on the quality and quantity of stormwater that runs off that land into Golf Course Creek then discharges into Sylvan Lake through Marina Bay. We evaluated the Water Balance methodology used by BC municipalities to model stormwater flows and concluded that the low probability of excessive lake contamination to cause chronic eutrophication did not justify a Society project expenditure of $10,000.

Wallpapering of the whole watershed with urban development would change the impact assessment considerably. A cumulative effects monitoring program is still required.

Contacts with Governments

We have reduced communications with municipalities and government agencies that do not add clear-cut benefits for the Society and our members. When the inter-municipal Sylvan Lake Management Committee reactivates the Cumulative Effects Management System project we will reassess our involvement. We continue to track watershed changes and report on watershed health indicators independently.

Alberta government agencies remain preoccupied with their internal affairs and have not been inclined to offer hands-on assistance to community stewardship groups like ours. We shared SLWSS accomplishments in this report to the 2017 Recreational Lakes community.