A Resident's Guide to Septic Systems. How septic systems work Environmental issues Guidelines

Transcription

1 A Resident's Guide to Septic Systems How septic systems work Environmental issues Guidelines Emptying

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3 Table of Contents How septic systems work Purpose of a guide on septic systems Septic tank installations and the Ville de Sherbrooke's responsibility Description of a septic system How does your septic tank work? How does a leaching bed work? Environmental issues Micro-organisms in the septic tank: crucial allies! Septic systems and their impact on streams and other bodies of water How can you tell if there is a problem with your septic system? Guidelines Water consumption Caring for the space around your septic system Use of certain products Products that impede bacterial activity Materials that take a long time to decompose Cleaning products Additives

4 Table of Contents (continued) Guidelines (continued) Precautions against freezing Abandonment of a septic tank Emptying Emptying procedure for septic tanks in Sherbrooke Conventional tank with a leaching bed Holding tank (hauled sewage system) Emptying procedures: Steps to take Before emptying During emptying After emptying Tips to make life easier Permanent accessibility to your septic tank 20 Information 21 4

5 Purpose of a guide on septic systems In 2013, there are more than 5000 septic systems within Sherbrooke's territory, more than half of which are located in the Borough of Rock Forest Saint-Élie Deauville. For many residents, this independent waste water management system may appear to be somewhat complicated, in terms of how it works, its impact on the environment, and how it's emptied, a responsibility shared between the Ville de Sherbrooke and property owners. We recommend you consult this guide to understand your septic system. In it, you'll find answers to many of your questions, including: How septic systems work How can I improve the efficiency of my septic system? How can I ensure that my tank is emptied easily and effectively? What are the signs of trouble? Septic systems and the Ville de Sherbrooke's responsibilities For the past 30 years, Quebec municipalities have been mandated by the provincial government to apply the Regulation respecting waste water disposal systems for isolated dwellings (Q-2, r.22). The regulation applies to residences with six bedrooms or fewer and other buildings that: generate a daily flow of waste water under 3240 litres are not connected to a sewage system. The regulation covers various aspects, including the issuing of construction permits, emptying of tanks, and the control of nuisances with regard to septic systems, for example. To meet its obligations, the Ville de Sherbrooke relies on a multidisciplinary team mandated to inform and provide support to residents who own septic systems. 5

6 How septic systems work Description of a septic system A conventional septic system consists of two components: a septic tank and soil filter, commonly referred to as a leaching bed. These two components make up an individual waste water treatment system (Fig. 1). Fig. 1 Individual waste water treatment system Leaching bed 6 Septic tank

7 How does your septic tank work? The septic tank is comprised of a reservoir with two chambers buried on your property (Fig. 2). The volume of the reservoir depends on the needs of the house involved. The first chamber (Chamber 1) separates the solids from the liquids through decantation: heavier solids settle to the bottom of the reservoir and become sludge while greases and fats, called scum, float to the surface. The second chamber (Chamber 2) contains water with fewer solids that is evacuated towards the leaching bed. How septic systems work Covers Outlet to leaching bed Connection to your property Scum CHAMBE R 2 Sludge Fig. 2 Simplified drawing of a septic tank H MB R C A E 1 The rate to the leaching bed varies according to the quantity of waste water sent. Under normal conditions, a septic tank is always full of liquid. Hence, whenever water enters the tank, a quantity of liquid flows out to the leaching bed. Role of the septic tank The role of the septic tank is to separate liquids from solids and retain sludge and scum, preventing them from blocking the leaching bed. In accordance with provincial and municipal regulations, and backed by studies, emptying the tank every two years is sufficient to ensure proper functioning of the leaching bed. However, certain guidelines must be respected (see Guidelines tab on page 11). 7

8 How septic systems work How does the leaching bed work? Liquids slowly run off towards the leaching bed from the outlet located in the tank's second chamber. The latter may be a standard leaching bed comprised of perforated pipes (Fig. 3a) or any other system with a filtering medium. This filtration improves the secondary or advanced secondary treatment according to the elements in place. Water then progressively infiltrates the ground or an embankment. Micro-organisms present in the soil digest some of the impurities and the purified water eventually infiltrates the ground water. The type of leaching bed selected depends on different factors: the nature of the soil, the profile and surface area of the leaching bed, the number of bedrooms in the home, etc. Hence, an expert assessment is required before you begin work. Next, based on the expert assessment, the Ville de Sherbrooke's building inspector will issue a construction permit for the modification or installation of a new septic system. This permit is issued in compliance with current provincial regulations. All septic tanks built since 2009 must be equipped with a pre-filter. The latter is located inside the second chamber, where the waste water exits to the leaching bed (Fig. 3b). If your tank has a prefilter, consider cleaning it after the tank has been emptied to reduce the risks of blockage. Fig. 3a Model of conventional leaching field Cover Outlet to leaching bed Pre-filter Chamber 2 8 Fig. 3b Model of tank with pre-filter

9 Micro-organisms in the septic tank: crucial allies! Inside your tank, micro-organisms feed on organic matter and break it down, reducing the volume of sludge and scum. These micro-organisms promote the optimal treatment of waste water and must be preserved, since their presence is a sign of an efficient system. Environmental issues Fig. 4 Micro-organisms present in septic tanks: sign of an efficient system! Did you know that a reduction in water consumption improves the treatment's effectiveness? In fact, the longer water is in contact with microorganisms, the better organic matter breaks down. 9

10 Septic systems and their impact on streams and other bodies of water When a septic system is malfunctioning or improperly used (by introducing excess water or undesirable products), the treatment is less effective. Thus, when the leaching bed malfunctions, water laden with contaminants (ex.: phosphorus or nitrogen) is expelled into nature and pollutes bodies of water, resulting in algae bloom (ex.: cyanobacterium) and a proliferation of aquatic plants. The discharge of fecal coliforms exceeding standards may also cause health risks. In certain cases, restricting the use of waterways is inevitable, primarily affecting recreational tourism activities. Environmental issues Did you now... that even if your septic system is not near a stream, it can still have an impact on it? In fact, ditches and ground water contaminated by your Comment remarque-t-on si on a un problème septic system will eventually reach waterways. avec son installation septique? How can you tell if there is a problem with your septic system? Different signs can indicate a malfunction of your septic system: The lawn covering the leaching field is exceptionally green and spongy Water in pipes takes longer to drain (sink, toilet, shower) Pipes and ditches emit sewage odours Grey or black liquids may surface on your property Traces of overflow may be visible around septic tank covers A water analysis of your well or that of your neighbour's reveals bacterial contamination. Most of these points are easy to check: the proper functioning of your septic tank is your responsibility. 10

11 Guidelines for an efficient septic system that respects the environment Several guidelines must be respected to promote the proper functioning of your septic system and extend its life span while respecting the environment. Water consumption The more we reduce our water consumption, the more we increase the efficiency of our septic tank! Consider saving water by repairing leaking faucets, choosing to take showers over baths, and installing a toilet with a smaller tank. Plan to do laundry over several days during the week instead of all at once during the weekend. In addition, run-off surface water from footing drains, gutters and pool water must NEVER be directed towards septic tanks. Do you have a water softener? Water used to backwash your water softener must NEVER be directed to your septic tank. The strong concentration of minerals can hinder the functioning of your septic tank. Guidelines Caring for the space around your septic system The leaching field is an important and fragile part of your system. To avoid compacting the soil and reducing its role as a filter, you must never drive heavy vehicles or park a car on your leaching field. The installation of children's play modules, gardens, and concrete or asphalt infrastructures on a leaching field is prohibited. In addition, trees and shrubs must be located at least two metres from the leaching field (see Fig. 5). To prevent erosion and absorb excess water, choose grass or other herbaceous plants for covering your leaching bed. Fig. 5 Recommendations to apply 11

12 Use of certain products The following products must never be disposed of through septic systems. Products that impede bacterial activity Materials that take a long time to decompose Guidelines Chemical drain cleaner Expired medication Large quantities of disinfectant (ex.: bleach) Motor oil Solvent and paint Water used to clean water softeners Note: Most of these products are accepted at ecocentres at no charge. Ashes Cigarette butts Cleaning products Condoms Cooking oil and grease Diapers Facial tissues, paper towels Hair Large quantities of organic material Pet litter Plastic materials Sanitary napkins, tampons Wet-wipes To dispose of these materials, the Ville offers several adapted services (rolling bins, ecocentres). For more information: sherbrooke.ca/environment 12

13 Products that impede bacterial activity Using products from this category results in eliminating micro-organisms in the septic tank that digest sludge and scum. Without these microorganisms, it is impossible to treat water properly and emit purged water. Materials that take a long time to decompose Materials that bacteria have a hard time decomposing can plug pipes or block your system's leaching bed and thus should be avoided. In-sink garbage disposal units should also be avoided since they significantly increase the amount of organic matter to be decomposed. Cleaning products While cleaning products destroy bacteria and viruses in the home, they are very harmful for micro-organisms in your septic tank. They often contain compounds that are difficult to decompose and hinder the effectiveness of the treatment. Consider reducing your use of soap and detergent. Opt for biodegradable products to limit the accumulation of environmentally-persistent products. Additives Certain businesses have developed products (ex.: enzymes) to improve the efficiency of your septic tank or leaching bed. Using these additives is at the discretion of the property owner. Guidelines According to the Ministère du Développement durable, de l'environnement, de la Faune et des Parcs (MDDEFP), using additives is not required to optimize the efficiency of your tank. In some cases, enzymes added to reduce sludge and disintegrate grease matter can attack the good bacteria and result in toxic run-off. The best way to use your system is to follow the advice provided in this guide. 13

14 Precautions against freezing Snow is a great insulator and contributes to protecting your leaching field from freezing. In the fall, before the snow falls, the Canadian Mortgage and Housing Corporation (CHMC) recommends spreading a foot of mulch over your leaching field, or simply letting the grass grow high. It should be noted that stagnant water in pipes or a low output of water over a long period of time is often the cause of frozen septic systems. To prevent this problem, it is recommended that the septic tank be emptied if you plan on being absent for a prolonged period of time in the winter. If, despite these precautions, your septic system is frozen, do not add products to your tank to fix the problem. Instead, contact an expert who will inject steam into the pipes. Abandonment of a septic tank When your septic tank needs to be abandoned, whether to install a new tank or because you're connecting to the municipal sewage network, after emptying your tank, you are OBLIGATED to: Guidelines Remove the septic tank from the ground or fill the tank with gravel, sand, earth or inert material. Prior to commencing work, contact a building inspector at a borough office (see page 21). 14

15 Emptying procedure for septic tanks in Sherbrooke Conventional tank with a leaching bed Since 2009, the Ville de Sherbrooke has been proceeding with the emptying of septic tanks within its territory, dividing the area into two sectors: A and B (Fig. 6). Sector A is delineated by the Magog River to the south, the St. Francis River to the east, Chemin des Écossais to the north and the municipal limit to the west. It includes a major part of the Borough of Rock Forest Saint- Élie Deauville, the entire Borough of Jacques-Cartier, and a small part of the Borough of Brompton. Sector B is comprised of the Boroughs of Brompton, Fleurimont, Lennoxville, Mont-Bellevue and a small part of the Borough of Rock Forest Saint-Élie Deauville. Between the months of May and October, tanks in sector A are emptied in odd-numbered years (2009, 2011, 2013, etc.), and those in sector B are emptied in even-numbered years (2010, 2012, 2014, etc.). Tanks are emptied every two years, a practice that meets the required regulations. A schedule for emptying the tanks of all septic systems in the targeted sector is set at the beginning of the season. Approximately ten days prior to the scheduled date, property owners are sent a notice in the mail informing them that they must clear the access to the septic tank. You are obligated to clear your septic tank for the date indicated. You could be charged additional fees should the truck need to return at a later date to empty your tank. Fig. 6 Division of emptying sectors within the territory A B B 3 Boroughs of: 1. Brompton 2. Fleurimont 3. Lennoxville 4. Mont-Bellevue 5. Rock Forest Saint-Élie Deauville 6. Jacques-Cartier Emptying 15

16 Holding tank (hauled sewage system) The Ville provides one service call every two years to empty your tank, regardless of the type of tank. The year your sector is targeted for emptying, if the date set for emptying your tank is not convenient, please contact the septic systems management coordinator as soon as you receive your notice to reschedule a better time for the service call. Please note that if you also have a conventional tank, it will be emptied on the same day as the holding tank. Your holding tank will likely need to be emptied more often, or at a different time than that scheduled by the city. All additional requests to empty tanks should be made directly to the company that covers the Sherbrooke territory at least three working days prior to the preferred date. You will be charged for the service call. We are pleased to inform you, however, that the city has negotiated a preferred rate with the contractor. Emptying procedures: Steps to take Before having the tank emptied: five steps to take 1. Clear the tank's two covers, two days prior to the date scheduled by the Ville. For example, if the visit is scheduled for a Friday, the covers must be cleared on the Wednesday prior. Please note that a minimum allowance 20 cm (8 in.) is required around each cover (Fig. 7). 20 cm (8 in.) Emptying 16 Fig. 7 Clearing of septic tank prior to emptying T W T F S C E

17 2. Make sure that there are no infrastructures (ex.: patio, wooden structures) or decorative elements (ex.: mulch, flowers) covering the tank. There should be no obstacles within a 1.5-metre radius around the tank or within 3 metres above the septic system (Fig.8). 3 m 1.5 m 1.5 m 1.5 m Fig. 8 Mandatory clearance zone 3. Clearly identify the location of the tank (ex.: use a stake) so that the company responsible for emptying the tank can easily find it (Fig. 9). Emptying Fig. 9 Identifying the location of your septic tank 17

18 4. Make sure the site is safe and accessible (unlocked fence, pets tied up if needed, tree branches cut). Your civic number must also be visible from the public road (Fig. 10). 123 Fig. 10 Visibility and access to your property 5. Refer to your septic system's manufacturer's instructions for directions on emptying the tank. For example, some leaching fields such as Bionest systems are equipped with a circulation pump that must be turned off during emptying to avoid damage (Fig. 11). Fig. 11 Manufacturer's instructions Emptying 18

19 During emptying You do not need to be on site during the emptying of your septic tank, unless otherwise requested by the Ville. In principle, the tank will be emptied on the date scheduled and you will be notified at least ten days prior to the visit. IMPORTANT Emptying begins as early as 7 a.m. Please note that the Ville de Sherbrooke empties septic tanks ONLY. If you have a secondary treatment system, its maintenance and emptying must be carried out by the manufacturer. After emptying The company emptying your tank will leave a doorknob hanger once the work is complete. If you did not receive one on the date scheduled for emptying your tank, call Make sure the site remains accessible until you've received confirmation of the work through the doorknob hanger. Emptying 19

20 Tips to make life easier Permanent accessibility to your septic tank Your septic tank must be accessible at all times to allow emptying. If you're frustrated by having to repeatedly clear your covers, consider a permanent solution. The following are examples of layouts recommended by the city. For tanks that are deeper in the ground, access risers should be installed. Place an insulating material over each tank cover that can easily be removed to allow emptying, and install an access riser at ground level (Fig. 12a). Access opening Ground Deflector Access riser Insulating material Deflector Scum Sludge Separator Chamber 1 Chamber 2 Fig. 12a For a deep tank, installation of an access riser over the covers Tank covers or covers added to the access riser for deeper tanks are then surrounded by a French drain to ensure that vegetation growth does not limit access (Fig. 12b). 20 Fig. 12b: Installation of French drains around each cover

21 Information For any questions, call To obtain a construction permit or to abandon a septic system, contact one of the offices below: Boroughs of Schedule Telephone Brompton Tuesday and Thursday mornings Fleurimont Lennoxville Monday afternoons, Tuesday all day, Wednesday afternoons, and Thursday mornings. Monday and Wednesday mornings Rock Forest Saint-Élie Deauville Monday to Friday Jacques-Cartier and Mont-Bellevue Monday to Friday Note: For these two boroughs, please contact the Urban Planning, Permits and Inspection Department. To report a malfunctioning septic system within Sherbrooke, contact a building inspector from the urban planning, permits, and inspection division of the Ville de Sherbrooke, at

22 For more information... Ville de Sherbrooke Web site: sherbrooke.ca/septictank Owner's manual from your septic system (consult the manufacturer) Ministère du Développement durable, de l'environnement, de la Faune et des Parcs (MDDEFP) Web site (French only): Canadian Mortgage and Housing Corporation (CHMC) Web site: Notes 22 Cette publication est aussi disponible en français

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