River Slick

Slick Coagulating Back Together

Thick Brown/Green River Slick

Rain Cannot Penetrate the Surface


•Slow moving oily slicks observed travelling down river in Zephyr Creek, Black River watershed – Georgina, York Region.

•Community documented occurrences of slicks coincide with observations of extensive biosolid (human waste) field applications upstream in Zephyr Creek.
•Ten documented occurrences of the oily slicks during summer 2014 related to major rain events, after the initial early summer biosolid application.
•Unique phenomena slicks on this river in 30 years of observation and 5 years of detailed monitoring.
•Community partners (Black River subwatershed) have documented similar phenomena on other area streams and rivers in other years.
SLSN Copyright 2014

Documentation included extensive field work by foot and canoe, that included:

–recording event occurrences and weather conditions, photographing, tests
–mapping spatial extent and movements of slicks , impacts of weather, time

Extensive photographic record of all events (10) June 9 – September 28, 2014 have been archived, and future analysis planned. Accompanying photos in the slides are representative of slick events.
Water samples of slick collected by members of MOEE, ZSLS and the South Lake Simcoe Naturalists (SLSN).
SLSN and ZSLS have planned continued monitoring and field work of the land/water interface in Lake Simcoe streams and rivers, including this site.

Slick Characteristics:

•Oily slicks have a silver sheen colouration which appears over the first 1 to 3 days of the slick moving downriver.
•Slick appears to be a combination of grease (brown) lipids and related compounds as well as bacteria, and potential viral components which are both typical of biosolids.
•Faint odour has been noticed by some observers, but not usually detectable and not reliably characteristic.
•Animal feces (wild species) in area (loose stools) indicate new bacteria source of contamination in the environment.
•Slick shape and integrity held together laterally with an extensive size spread ranging up to 130’ long by 30’ wide.
•Oily film rides slightly under the water surface and is resilient to light rain events (physical/chemical bonding).

Temporal Pattern & Change:

•Over time the colouring shifts from green to brown as it picks up other biological components by air and water. Slicks darken to brown but remain oily in appearance and behaviour. At this point the slick becomes stronger bonded
•As algae becomes a greater component of the slick’s composition over time and distance travelled, the physical and chemical composition of the slick changes and reaction to disturbance slows.
•It is proposed these slick events enable bacteria and algae to interact in complex ways in slow moving, sediment-laden streams, creeks and rivers and are associated with water-piping tiles in fields, that leads to exploding eutrophication conditions (commonly documented in biosolid environmental literature in the U.S and other countries).
•When physically disturbed:
–slick surface opens up
–appears to chemically and physically reorganize
–quickly closes up again
-see video above

Spatial Patterns & Change:

•Slicks thicken internally, become dense dark floating masses over time and travel downstream. Often parts of the original slick become entrained in meanders.
•These masses move slowly (can take weeks to travel several kilometres) and stay together until wind, rain and river debris break them up as they move down river, slowed by interferences such as overhanging tree debris, log deadheads etc.
•Significant wind causes intact slick to move great distances, including upstream, downstream and across channel in one integrated slick as observed on numerous occasions.
•The slick can concentrate in river meanders where movement stalls and aging of the slick proceeds, the light silver sheen darkening to brown algal formations.
•Slowly the slicks start to look more biological in composition and the algae can be entrapped in riverine submergent plant material and behind logs and other riparian debris in the river course.
•Suspected decomposition occurs and material sinks depositing oil, grease and bacteria to the water column and eventually the river bottom (observed).
•These river slicks slowly make their way to larger streams, rivers and eventually Lake Simcoe, transporting a wide range of algae and diatoms, bacteria, Phosphorus (P) and Nitrogen (N) that heightens eutrophic conditions in these water courses. (observed and documented).

Causes & Environemntal Factors:

•Extensive biosolid application in areas upstream occurred several days prior to the first slick event in 2014.
•Local agricultural fields and soils are sandy with reduced A and B profiles, and were uncovered without turf for much of spring and summer.
•Extensive past drainage conveyance systems in place in agricultural turf fields undoubtedly enhance field infiltration and runoff to water courses. In 1st – 3rd order streams, these conveyances in turf fields with no or minimal field and landscape restoration plantings (the case in the Zephyr Creek example) will contribute to rapid drainage of biosolids following rain events.
•Slick occurrences were correlated to major rain events throughout summer and early autumn (detail documented).
•Heavier, more intense and higher volume of rainfall, leads to more intense, larger and persistent slicks(documented–10 occurrences).

Headwaters Stream Protection:
Need for Continuing Research:
•Continued physical science research on slicks at current site and other similar sites in the watershed.
•Further slick water sampling and testing of biochemical composition and water quality at existing and future identified phenomena locations.
•Detailed analysis of physical geography of river and surrounding watershed of field site, and at other locations focusing on 1st – 3rd order stream locations in agricultural conditions.
•Spatial-temporal documentation, monitoring and landscape ecology research and predictive analysis of slick events, weather and related land use. Broad based landscape analysis of comprehensive watershed conditions and characteristics related to future policy and on-site management recommendations of Headwater Stream Protection in the Lake Simcoe Region Conservation area and Southern Ontario.

Need for Planning Review:
•Design recommendations for naturalization/restoration of 1st-3rd order tributary streams in Lake Simcoe watershed.
•Current Lake Simcoe Region Conservation Authority (LSCRA) Policy Review recommendations by SLSN and Ecojustice have asked for comprehensive review and formulation of new Headwater Protection Policy, strategies and restoration implementation.
•Pursuit of tightening planning and policy improvement in the whole Lake Simcoe watershed related to current unsustainable and harmful land use practices related to these observed oily slick events. This work should investigate reviewing all of Southern Ontario where biosolid material is applied to agricultural fields.
•Improve recognition of links between biosolid application, land use and river sources of:
–Nitogen (N) and Phosphous (P) – Triclosan
–Lake Simcoe eutrophication – Bacteria, Viruses
–Pharmaceuticals – Leptothrix

Watershed Headwater Protection, Issies & Policy:

•Community engagement in the broader watershed has revealed many similar slick events in other streams and rivers in other years. These historical events are being documented and considered for future research investigations. It is expected these slick events are occurring throughout other areas of Southern Ontario but are not being well documented or appropriately investigated.
•Headwater or source water protection, along with wetlands, is crucial to ensure long term sustainability. Stronger policy that recognizes the need for headwater protection is essential for Lake Simcoe watersheds. This is important at the small stream and small wetland level.
•A new and comprehensive Headwaters Policy for the Lake Simcoe Region Conservation Authority (LSRCA) is required. This has been acted on by SLSN with a Policy Review Report in September 2014 with recommendations to LSRCA.
•A new policy would ensure that the current landscape gaps, specifically the absence of drainage feature guidelines or sufficient policy to ensure the protection of unconfined and non-apparent valley features, especially those with water piping tiles, and applying biosolids be addressed with sound new policy and appropriate field investigation.
•The Toronto and Region Conservation Authority (TRCA) has recently developed detailed drainage feature guidelines. A similar set of guidelines could be incorporated into a new LSRCA headwater protection policy.

Testing & Monitoring:

•Rigorous, consistent field investigations and monitoring in low undulating agricultural headwater stream locations by agencies including MOEE, OMAFRA and LSRCA. This investigation should be random and unannounced.
•Expand on current ad hoc response to community complaints including improved response time for these episodic river slick events.
•First to Third (1st-3rd) order streams in intensive agricultural regions in the Lake Simcoe watershed require intensive monitoring and auditing to determine where and how source water contamination is occurring. This analysis could be expanded to all of Southern Ontario.
•Limited documentation on river slicks and relationship to P and N loading in Ontario streams related to biosolid application potentially represents a major gap in river water quality and issues such as eutrophication, bacteria, virus and pharmaceuticals entering river systems
•Extensive and focused water testing and analysis by MOEE for biosolid leakage into creeks, streams and rivers focusing on biosolid indicators like Leptothrix.
•If MOEE is not able to provide required testing need to consider alternative solutions and resources and other planning and monitoring operational arrangements.

Immediate Actions Needed:

•Organized and consistent Citizen Science observations and monitoring of River Slick Events
–Recruitment of landowners, naturalists, hikers and cyclists to provide information on water quality in local creeks, streams and rivers in Lake Simcoe agricultural areas and beyond in Ontario.
–Focus on sites where biosolids (human waste) are known to be applied including intensive agriculture and turf farming locations. Consider community notice system before biosolid application for human and wildlife health reasons.
•Consistent and rigorous monitoring of water courses for the effects of biosolid application
–Agencies including MOEE, OMAFRA need to have better and faster response times to watershed problems as they arise.
–Agencies need to be proactive including biosolid marker test methods and reporting capabilities as well as random inspections of applications.
•Restoration of upper watershed 1st to 3rd order streams including:
–Creation of adequate vegetation buffers, corridors etc. in areas of unconfined and non-apparent valley features where there are water piping tiles and biosolid applications, especially in locations of intensive agriculture and turf farming
•Comprehensive Master Drainage Plans need to be undertaken for all watershed rivers, streams and creeks in the Lake Simcoe watershed.
–All water conveyances especially piping/tile in field systems need to be reviewed, documented and monitored regularly.
–Future drainage projects should be halted until a comprehensive review of tiling and biosolid applications can be completed for areas where it is applied.
•More extensive and focused water testing and analysis by MOEE for biosolid leakage into creeks, streams and rivers. Appropriate test methodology and capability should be routine.
•Review and consider future changes to the Ontario Nutrient Management Act.