More Turbid Stormwater from the Town Enters Sylvan Lake

More intense rainfall has added an additional load of entrained solids from stripped and cleared land and exposed development excavations within the Golf Course Creek catchment.

Precipitation reports from three weather stations show the range and intensity across the Central Alberta area west of Sylvan Lake (click to enlarge the image):

Three Station Precip 2015-08-13 to 23

Some of that turbid stormwater runoff from that recent rain was held up in the detention pond at 60th Street and 48th Avenue:


Additional photos in this album follow the turbidity into Golf Course Creek, through the Sylvan Lake Golf and Country Club irrigation pond, and into Marina Bay and Sylvan Lake through the culverts under Highway 11A.

Sylvan Lake Precipitation and Stormwater Runoff in 2015

How much precipitation has fallen on the watershed in 2015? Has is been lower, higher or about average?

The answer, according to data from Alberta Agriculture’s Hespero weather station west of Sylvan Lake we have received just about the typical historical amount. This graph shows the 2015 cumulative precipitation (red) compared to the average curves for the Hespero (blue) and Red Deer Airport (yellow) weather stations. Click to enlarge the figure:

Hespero Precip 2015-01-01 to 08-17

Because of the wide range of precipitation at points on the ground the 2015 curve is just representative. In Alberta, incident rain can very significantly within short distances. Still, over time it averages out. We will continue to use the Hespero station as our reference as it is generally upwind of the watershed and cloud systems tend to blow in from the west. The Alberta Agriculture database does not report annual accumulated precipitation for the Lacombe Airport.

What do the data mean? We have received a little more than 35 cm of precipitation since the beginning of the year.

If we only look at the data since May 1:

Hespero Precip 2015-05-01 to 08-17

rain has fallen intermittently with lengthy dry periods in between. Those 20-30 mm rains have caused excitement and they have tested the Town of Sylvan Lake’s stormwater system. The strip-mined areas of town, the land under development at the south end, have been susceptible to erosion and runoff that has caused Golf Course Creek to become turbid as reported in a separate post.

Once solids become suspended in a flowing or turbulent water body there are two solutions to restore water clarity:

(1) Slow down the flow and allow the particles to settle according to Stokes’ Law. Heavier coarse particles settle rapidly. Very fine ones like clays can take decades. Stormwater detention ponds are supposed to provide extra settling time just like tailings ponds do at mining operations.

(2) Apply separations technologies like thickeners, cyclones, centrifuges and filters to speed up the separation. Non toxic flocculants can be added to increase particle size by agglomeration and to increase the Stokes’ Law settling rate.

Of course if eroded particles are prevented from entering the stormwater system at the source then Sylvan Lake’s water will remain clear as an elementary school student reminded us:

FRS-Jade T-Kendall-v2

Contaminating water bodies can be a serious offense under Alberta’s Water Act. The best practice is not to let it happen.

High Tech Stewardship: Watchdogging from Space

Like to be nosy? Join the satellite spy team. Use Google earth to keep an eye on the Sylvan Lake watershed. Monitor and report on land uses and changes. Use Street View and check it out at ground level.

What will you see? Applications of Non-Beneficial Management Practices. The consequences of NBMPs. Actions that are contrary to the best urban and agricultural land use recommendations.

The map pins in the first image locate a few NBMP examples. The Google Earth image combined with on-the-ground confirmation provide evidence of shoreline lots that have been clear cut edge-to-edge and lake-to-road in Summer Villages. Locate the source of recent Town of Sylvan Lake soil erosion that was suspended in stormwater, and discharged into Sylvan Lake through Marina Bay.

Beneficial Management Practices, BMPs, are recognized too. Responsible construction on wooded lots is possible. Permeable, instead of paved, road surfaces help precipitation infiltrate and maintain the groundwater supply while reducing stormwater runoff into the lake.

To view the pin points and associated data in detail, request the master watchdog .kmz file for importing into Google Earth. Active members may request the free file by contacting us at

NBMP Cases at Sylvan Lake 2015

 Click on the image to expand it.

This image shows the stormwater route that conveyed suspended fine soil particles into Sylvan Lake from an up-slope development.

For a while, pickerel in Marina Bay couldn’t see the sun.

Sediment Discharge-GCC-2015

Click on the image to expand it.

Heavy Rains Erode Soil and Contaminate Sylvan Lake

1-DSC_0056 2-DSC_0051 3-DSC01214

Recent heavy rains have caused erosion of construction sites in the Town of Sylvan Lake (TSL) and transported fine particulates into the lake through the stormwater system and Golf Course Creek. The flow discharges into Marina Bay and then into the lake as a plume of very fine suspended solids that cause water quality to deteriorate as these photo show.

The TSL’s investigation of the source of the release was reported to Council at the August 8 meeting. Clearly there is scope for improved containment of runoff from construction sites in the watershed and stronger regulatory action with appropriate penalties.

Alberta’s Hotline for citizen reporting of contaminant releases is:

Energy & Environmental Response Line

24 Hour Hotline: 1-800-222-6514

This case history is further proof that the Two Laws of Watersheds really do apply in the real world:

  • Water flows downhill
  • Stuff from the land ends up in the lake

Mapping the Sylvan Lake Watershed

The SLWSS mission is simple: Protect the water quality of Sylvan Lake. To do so, it helps if we know what we are talking about. Due diligence for sound decision-making requires knowing lots of stuff.

And there is plenty to know about as publicly available data confirm.

Satellite and aerial images of the lake and the surrounding land are helpful to show the agricultural and urban environments that affect the state of the watershed.

Sylvan Lake Watershed Boundary.v2

Click to enlarge

The two major tributary catchments for Golf Course Creek and Northwest Creek are easily seen at high resolution. The boundary of the watershed is shown as a white line. The significance of that perimeter is that precipitation falling inside the line will potentially flow into the lake because of the contour of the terrain, carrying dissolved and suspended minerals, nutrients and contaminants with it. Note that the eastern section of the Town of Sylvan Lake lies outside the watershed boundary. Much of the stormwater, and all of the waste water, that is collected by the Town is diverted eastwards and out of the watershed.

Geographic Information System (GIS) software can consolidate and display layers of large sets of data as maps. The map below is a  multi-layer GIS graphic that contains several categories of data including the topography, roads, the Alberta township grid, two railway berms (that interfere with Golf Course Creek catchment flow and create a series of wetlands in the gully between the two), pipeline networks, plus the many regional tributary flows that are highlighted boldly in blue.

Watershed Master Map.v2

Click to enlarge

Protecting the lake and watershed starts with knowing the facts. The SLWSS, and the watershed municipalities, have the knowledge about land use and the surface and groundwater sources to do so.


Keep Nutrients on the Land……..Not in the Lake

Alberta Agriculture and Forestry (AB Ag) research on nutrient transport has evolved over two decades is relevant to the situation in the Sylvan Lake watershed. About 67% of the land area within the watershed boundary is used for agriculture. Those uses are also diffuse sources of nitrogen (N) and phosphorus (P) nutrients as a result of the cycle of growth and decay of organic material on the land. During the growth phase plants extract needed elements from the soil, particularly from the inter-granular water in the root zone that contains soluble building-block species of N and P. Plant decay, promoted by organisms in the soil, is continuous and releases cell nutrients back to the soil inventory for re-use. Farmers know that and use soil test chemical analyses to determine how much fertilizer must be added to grow the next crop, without adding an excess. Growing and harvesting food crops also mines the soil and removes nutrients that must be replaced to maintain crop yields.

P in Cell Walls

Phosphorus is an important element in phospholipids that form cell walls that can decay and disperse.

P in DNA

Cell DNA contains phosphate groups that can also be recycled into the environment.

AB Ag has found that the concentration of nutrients in the top few centimetres of soil is also an important source of available N and P in runoff into streams and water bodies. So is manure that is stored for use or dispersed on the land as nutrient-rich fertilizer. Typically, nutrient levels are the highest in spring runoff, then drop as the ground warms up and plants grow, trap, and retain N and P. The next graph shows SLWSS results from water quality sampling of Golf Course Creek in 2014 that confirm the AB Ag finding. Data from other Sylvan Lake tributaries follow the same pattern. The lowest N and P concentrations in those streams have always been above those measured in Sylvan Lake and summarized by ALMS in Lakewatch reports. So the natural nutrient cycle on agricultural and forested watershed land loads the lake with nutrients on an annual cycle.

N and P in GCC

SLWSS water quality sampling results for Golf Course Creek in 2014. High levels of N and P were found in Spring runoff. Nutrient concentrations through the summer remained above those observed in the lake itself.

The element phosphorus is often the critical limiting factor that controls the trophic state of lakes. Sylvan Lake’s long term average Total Phosphorus analysis of 21 micrograms per litre keeps the lake in a meso-eutrophic state with typically low chlorophyll-a concentrations associated with suspended plant matter. Algal blooms have been rare. The watershed community counts on it staying that way. That is why AB Ag’s application of field research findings and modeling studies into practical best management practices are important. Phosphorus is better fertilizing plants on watershed land than algae and plants growing in Sylvan Lake.

Instead of presenting a technical review of the excellent experimental and modeling nutrient transport work of AB Ag, the department’s publications can speak for themselves. Here is an introduction to a few that illustrate the scope and caliber of that research. Reports on three field studies:

are complemented by a fact sheet, a link to the very important Soil Phosphorus Limits Project web page, and a Phosphorus Sources and Sinks analysis:

The latest AB Ag approach to analyzing nutrient transport in Alberta watersheds will soon be available in a series of reports that will be posted on an Alberta Agriculture and Forestry publications web page. This post will be updated when those documents are approved for release.

An important Sylvan Lake watershed question, not yet answered, is about the magnitude of annual N and P nutrient loading of the lake from the surrounding agricultural land. The AB Ag work provides the basis for addressing that lake nutrient loading issue. Attempts to estimate the phosphorus and nitrogen loads by measuring tributary water quality and cumulative flow have yielded unsatisfactory results. Consequently, knowledge of nutrient transport processes in the Sylvan Lake watershed are inadequate to allow due diligence predictions of the impact of urbanization on the scale imagined in municipal plans.

The Alberta Geological Survey Takes the Groundwater Lead with the Sylvan Lake Project

The Alberta Geological Survey (AGS), now a part of the Alberta Energy Regulator (AER), is the Sylvan Lake watershed’s newest best groundwater friend.

We know that groundwater is important because everyone in the Sylvan Lake watershed extracts and uses well water. That underground supply of water is also critical for the rest of Alberta as the report “Groundwater in Alberta – An Assessment of Source, Use, and Change” explains.

The full scope of the Sylvan Lake project was introduced at the Watertech 2014 conference by Dan Palombi in the AGS-AER presentation “Integrating Numerical Modelling into the Groundwater Policy Assurance Process”.

The AGS groundwater team has built upon the major Edmonton-Calgary Corridor groundwater study and zeroed in on the Sylvan Lake-Gull Lake-Red Deer region. Phase 1 of the “Sylvan Lake” project investigated the geology under about 600 square kilometres of land that includes Sylvan and Gull Lakes and some of the Red Deer River valley. Those results are published in the AGS report “Three-Dimensional Hydrostratigraphic Modelling of the Sylvan Lake Sub-Basin in the Edmonton-Calgary Corridor, Central Alberta”.

Phase 2 takes the detailed geological data from Phase 1 and feeds that knowledge into a MODFLOW groundwater simulation that includes our watershed.  The model utilizes that United States Geological Service gold standard groundwater numerical modelling code and links it to the open source software iMod. By zooming in to our valley in 3-D it becomes easy to understand the groundwater dynamics. No analysis will get better than this, especially because the AGS is collaborating with the not-for-profit Dutch agency Deltares as a top-gun expert partner.

Applications that will interest SLWSS members include evaluation of the impact of land use changes on groundwater supplies. Pumping more water for domestic and commercial uses than can be replenished by infiltration, then exporting it from the watershed in wastewater will deplete the underground inventory over time. Urbanization of the watershed will also divert more precipitation into stormwater collection systems and export it to the Red Deer River instead of into Sylvan Lake. Those impacts can also be evaluated by combining surface and groundwater flows in an advanced GSFLOW analysis.

The SLWSS has an opportunity for our “Citizen Scientists” to become actively involved with field data collection to support the AGS’ Sylvan Lake project. Monitoring water well levels, and collecting and submitting well water samples for water quality and geochemical analyses, might be needed as the Sylvan Lake project evolves. Rocky View County has already demonstrated that it can be done by involving  its residents in a groundwater project to monitor well water levels.