The riparian strip is the edge of natural vegetation bordering a lake. It is a transition zone between aquatic and terrestrial environments. It is very important not to disturb the riparian vegetation band all around the lake. This band is a filter against pollution. It acts a bit like the filter of an engine retaining all the sediment, impurities and detritus that would otherwise flow directly to the lake. The mixing of roots and soil produces a natural barrier that plays several extremely important roles for water quality and provides filtering of all runoff from roads, lands and upstream watersheds. Provincial regulations exist and are applied by Quebec municipalities. If the vegetation band is disturbed, restoration techniques exist. There is evidence that the more vegetated banks are, the more protected lakes and streams are.

Behind the bright colors of the fireworks, it's all a cocktail of chemicals that explodes. Essentially,  fireworks  contain black powder used for  fuel, which is composed of  coal, sulfur saltpetre and an oxidizing agent (usually potassium perchlorate).Fine metallic particles  are also found, which give their  colors to the fireworks. For example, blue comes from the  copper, red from distrontium  or  lithium, and bright green or white from  dibarium. These substances can be a source of significant health problems. 

During its explosion, the firework releases millions of  fine particles  of heavy metals into the atmosphere  which generate significant pollution, much higher than that from  automobile traffic. The particles thus released are deposited in the environment and in our lakes. Phosphorus is another released substance that persists in our lakes and affects vegetation and fish.  Burning of the  black powder  also causes a significant release of CO2. A fireworks display of 30 tonnes of powder thus throws 14.7 tonnes of CO2 into the atmosphere, the equivalent of a 67,000 km journey by a car using gasoline.

Studies to date on the subject are not yet numerous and do not all agree on the impacts on human and environmental health. The big difference between fireworks for urban and competitive shows and private fireworks is that private fireworks are often fired at a low altitude. Not having time to disperse in the atmosphere, their metallic and chemical compounds fall very quickly into the water and remain in the sediments at the bottom of our lakes. Added to this is noise pollution for our neighbors, risk of fire and stress in animals. For these reasons, several riparian municipalities now prohibit the use of fireworks or have strict regulations requiring permits or limiting the use on certain holidays.

Applying fertilizer on land near watercourses is very detrimental to aquatic ecosystems. In fact, these fertilizers contain a lot of phosphorus, a food substance for plants of all kinds. Rainwater carries phosphorus directly into the lakes and feeds algae and aquatic plants, which thrive. A high level of phosphorus also helps to accelerate the aging of the lake (eutrophication).

It is also important to note that organic fertilizers (compost) are absolutely not suitable for lands adjacent to water bodies. Even if they do not leave chemical residues in the soil, these organic fertilizers contain phosphorus, which is likely to enrich the lake in the same way as chemical fertilizers.

Pesticides and herbicides play the same damaging role for the environment, since they are rich in phosphorus. In addition, they contain chemicals that can be hazardous to health and potentially carcinogenic. The use of pesticides in Quebec is supervised by the Ministère de l'environnement, de la lutte contre les changement climatique, de la faune et des parcs (MELCCFP).

In short, it is essential not to use any type of fertilizer, be it natural or chemical, or any pesticide or herbicide, so as to protect our lakes and prevent them from degrading further. Fertilizers contain nutrients, including phosphorus, which promote faster plant growth. Unfortunately, they also promote the growth of aquatic plants and blue-green algae in lakes and streams.

Several municipalities have already legislated to this effect by banning or strictly controlling the use of chemical or biological fertilizers and pesticides in their territory.

Since wood is an organic substance, it enters a biological cycle that will irremediably lead to a degradation of its substance. This degradation occurs when the wood is exposed to mold, insects or bacteria. To counteract and slow down this phenomenon, there are various treatments involving the use of chemical substances. These treatments are intended to preserve and protect the pieces of wood in order to slow down the biological degradation. However, all chemicals used in the treatment or preservation of wood have special toxic characteristics because of the substances they contain (including arsenic, chromium, copper, boron, pentachlorophenol [PCP] and creosote).

The main concerns regarding the use of treated wood in the aquatic environment relate to the effects of preservatives leaching onto aquatic organisms and affecting water quality. In order to limit the release of harmful substances into surface waters, the use of any chemically treated wood in the aquatic environment is not desirable where alternatives are available. As indicated in MELCCFP's "TREATED WOOD MANAGEMENT GUIDELINES", aquatic structures must be made from materials other than treated wood, or from wood that is naturally resistant to putrefaction, such as cedar, larch and hemlock, or with plastic materials, metal, cement or composite materials.

Septic installations that are not in compliance with the by-law (regulation Q-2, r.22) or that are poorly maintained contribute to the discharge of contaminants into the receiving environment, in particular phosphorus, which is the nutrient responsible for the aging (eutrophication) of lakes and watercourses. An important contribution of this nutrient in a lake has the effect of increasing the proliferation of algae, aquatic plants and cyanobacteria (blue-green algae). Non-compliant or poorly maintained septic systems can also be the source of bacterial contamination of groundwater or well or source water used to supply drinking water. To find out if your septic installation threatens the health of our lakes, we invite you to read the CRE des Laurentides Septic Installations Guide (see Documents) and learn how to properly maintain your facility or how to check compliance.

Since April 2017, Decree 306-2017 aims to offer several new solutions to the owners of existing isolated residences and also offers support to the Government of Quebec through the implementation of a new refundable tax credit for the upgrading of residential wastewater treatment facilities to standards. This tax credit, which is in effect for 10 years (2017 to 2027), is intended to provide financial support to homeowners who must undertake repairs to their septic systems. The financial assistance granted by this tax credit, which may reach $5,500 per eligible dwelling, will be equal to 20% of the portion exceeding $2,500 of eligible expenses paid by an individual for bringing sewage treatment facilities in his or her principal residence or cottage to standards. For more information, visit the Association of Construction and Housing Professionals of Quebec (APCHQ) and Revenu Québec (see references below).

Dysfunctional septic installations represent a very important risk for the environment, particularly for the quality of drinking water and the health of water bodies. Leaks can contaminate an aquifer or cause an episode of blue-green algae in a lake. To protect its lakes, the Municipality of Messines has for several years been rigorous in managing the territory's septic systems.

Phosphate detergent products have a great deal of responsibility for disturbing the environment, as they act as true fertilizers. In fact, when drained with wastewater during washing cycles of a dishwasher or a washing machine, or with the rinsing water for cleaning, shampooing and conditioning, etc., they enrich the organic matter and upset ecosystems. They cause asphyxiation of the lakes by promoting the multiplication of algae and by increasing the production of aquatic plants. All products containing phosphates should be eliminated from our daily cleaning. Phosphates are compounds that contain phosphorus. This has an important role in the eutrophication phenomenon (aging) of a lake because an excessive intake of phosphorus can accelerate it. Too much phosphorus intake can also create favorable conditions for the development of cyanobacterial water blooms and the proliferation of aquatic plants, especially when the surface water temperature is relatively high and there is a lack of water. Oxygen dissolves in the deep water layers of the lake. It is recommended that we use products and soaps certified to be without phosphates for all housecleaning and body care. Some countries prohibit the addition of phosphates in cleaning products. This is the case in Switzerland, for example, which since 1986 has banned the addition of phosphates to laundry detergents for textiles.

For more detailed information about phosphates, consult the reference documents.

The Municipality of Messines introduced, in 2017, a new regulation making it mandatory to wash boats before launching them in any lake in its territory. The goal is to preserve the environmental quality of aquatic areas and the integrity of shorelines by preventing the introduction and spread of invasive alien species from one lake to another. By definition, an invasive alien species (EAS) is a plant, animal or micro-organism (virus, bacterium or fungus) that is introduced outside its natural range. If it is established or spread, it can pose a threat to the environment, the economy or society, and it can sometimes be very difficult to get rid of these intruders. Thorough cleaning of the boats and engines of any soil, leaves, plants or roots before they are put into the water will minimize the risk of contamination from one lake to another.

For additional information, consult regulation number 2018-347, regarding the washing of boats and access to lakes and waterways.

To best understand how boats influence the water quality of a lake, we must first understand the path of phosphorus in a lake. Phosphorus is an important nutrient responsible for aging bodies of water. Phosphorus comes from several diffuse sources (wastewater, fertilizer, fireworks) or point sources (agricultural discharge, erosion). Part of the particulate phosphorus and soluble phosphorus that attaches to the particles precipitates to the bottom of the water, the lake acting as a settler. This phosphorus is normally trapped in sediment and becomes unavailable to lake organisms.

When motorized vessels travel in shallow water, their passage, even at low speeds, affects sediment in the water column. Phosphorus, which is attached to the fine particles of the sediments, then becomes accessible to organisms in the lake. In addition, suspended particles promote the storage of solar energy, which contributes to the warming of the lake water, further promoting the growth of algae and aquatic plants.

Using Secchi's disk water transparency measurement daily has demonstrated that boating has an effect on the water quality of a lake. In fact, the simple comparison between weekly readings versus weekends shows a decrease of about 10% in the transparency of water for two American lakes (Anthony and Downing, 2003, Asplund, 2000). In addition, this reduction in transparency translates into a reduction in visibility for fish, which can impact predation performance for sight-hunting species, which then can lead to decreased productivity of populations.

Several researchers have focused on measuring this effect as a function of water depth. Asplund (2000) notes that an effect can be felt up to 3m deep, but it seems that activity in the water has the potential to resuspend particles as deep as 4.6m according to Beachler and Hill (2003). The most interesting finding is that intermediate velocities cause the greatest increase in turbidity and, incidentally, the greatest displacement of water at the sediment interface.

Intermediate speed navigation is known to produce the biggest waves. These are maximum when the boat is moving at the so-called hull speed and in particular that speed reached just before transition, called planing. In general, recreational boating generates waves with greater erosion potential than those caused by wind. This statement is based in part on the calculations of Bhowmik et al. (1991), which show that a wind speed of 72 km/h is necessary to generate waves of 0.3m height, whereas a motorized boat commonly produces a height between 0.3 and 0.4 m. Sustained winds of this force are rather rare in our continental regions.

The particular case of wakeboats: Some boats can be used for wakeboard (similar to water skiing) or wakesurf, which is to create a wave of sufficient magnitude to surf on it. Following a study of Memphrémagog and Lovering lakes, Mercier-Blais and Prairie (2014) concluded that the waves generated for wakesurf are the ones causing the most riparian erosion. Note that all the displacements by this type of boat cause waves likely to erode the banks. Their study concluded that to fully mitigate the effect of waves, wakesurf should be practised more than 300m from the shores.

Making a campfire too close to the lake, in the riparian strip or on the beach generates residual ashes that will eventually be washed into the lake by rainwater or waves. Ash generates significant amounts of nutrients such as phosphates, nitrates and potash as well as pollutants such as heavy metals. These nutrients promote the proliferation of algae and aquatic plants and contribute to the lake’s aging. For this reason, it is strongly advised to avoid making a campfire on the waterfront (where lake water can cover land). Several municipalities have already legislated this. To avoid the risk of fire and pollution of rivers, it is therefore strongly recommended to use metal fireplaces specifically designed for wood fires far from the shoreline. It is not advised to make open air fires directly on the ground and leave ashes on the spot.

The easiest way to dispose of the ash in an ecological way is by depositing the cooled ashes in a paper bag or in a certified biodegradable bag and then putting them in the garbage.

Some recommendations to prevent swimmer's itch:

• Limit contact with water, mainly in areas where vegetation is abundant; when getting out of the water, dry your skin by rubbing it vigorously with a towel.
• Always avoid letting the skin dry in the sun or in the open air.
• Avoid feeding aquatic birds.  

In addition, good practices also aim to avoid transporting environmental problems of our neighbours into our lakes. The best way is to ensure that boats are thoroughly cleaned of all plants, branches, leaves, dirt or other debris when returning from one lake to another to avoid contaminating our lakes. The new regulations for washing boats aim to limit contamination from one lake to another.