Fisheries and Oceans Canada-Saskatchewan District 2011 Post-Flood Shoreline Restoration and Stabilization Protocol

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1 Fisheries and Oceans Canada Pêches et Océans Canada Fisheries and Oceans Canada-Saskatchewan District 2011 Post-Flood Shoreline Restoration and Stabilization Protocol 1.0 Introduction Valid until March 31, 2012 The Province of Saskatchewan has experienced widespread flooding in the spring of As a result, there has been a substantial amount of flood damage to residential and recreational properties at numerous lakes throughout the province. In response, Fisheries and Oceans Canada (DFO) Saskatchewan District has developed a protocol to help guide and assist property owners who want to undertake certain types of shoreline activities in response to this flooding event. The purpose of this protocol is to describe what types of projects apply, the conditions under which property owners may carry out their projects and the mitigation measures that need to be incorporated into these projects in order to avoid negative impacts to fish and fish habitat. Provided the conditions of this document can be met, further review by DFO is not required. However, DFO requests that proponents wishing to utilize this shoreline stabilization document notify the nearest District Office prior to starting the work (see attachment for contact information). It is important to note that this document is not intended to apply to all types of projects that may be undertaken in response to flood damage. In particular, it does not include: industrial or commercial development properties; the reconstruction or installation of vertical retaining wall structures (i.e., concrete, wood, gabion baskets, sheet pile, etc.), located at or below the ordinary high water mark (OHWM) 1. large vertical erosion /slumping shorelines which require some form of geotechnical/engineering input into the stabilization design; projects that require infilling into the water beyond where the shoreline existed prior to the 2011 flood event; and, the replacement/repair of other types of infrastructure such as boathouses, boatlifts and docks. 2.0 Shoreline cleanup The general cleanup of debris from the shoreline due to elevated water levels is considered low risk to fish and fish habitat. However, the following mitigations should be followed while undertaking this work: Care is to be taken to minimize any further damage to shoreline areas when removing or hauling materials, especially if heavy machinery is being used. 1 The OHWM refers to the usual or average level to which a body of water rises at its highest point and remains for sufficient time so as to change the characteristics of the land.

2 Overhanging rooted vegetation, exposed plant roots and rocks located along the shoreline and below the OHWM should not be removed as they provide habitat for fish and help to stabilize the bank. Dispose of all permanently removed materials in an appropriate area where they cannot re-enter the waterbody. You should consult with your local municipality or Ministry of Environment office regarding appropriate disposal sites for potentially hazardous materials (e.g., chemical containers, propane cylinders, treated timbers, etc.). Where sandbags have been used for flood protection they should be removed from the area after they are no longer needed. Check with your local authorities regarding disposal plans for sandbags. The sand from the sandbags should not be dumped into or around the waterbody. Depositing sand into the lake or on the shoreline can harmfully alter or destroy fish habitat. Depending on its source, sand can contain harmful substances, like road salt, that are prohibited from entering the lake. Sand may be deposited on your lot above the high water mark as long as the sand is effectively contained so that it cannot erode into the lake and its origin is known to prevent leaching of any contaminants into the water. 3.0 Shoreline stabilization Littoral areas located adjacent to lake shorelines are often highly productive components of aquatic ecosystems. As such, any disruption to the productive capacity of these areas, either through improper stabilization techniques, or by allowing excessive erosion to continue, can result in significant impacts to fish and fish habitat. An eroding or slumping shoreline may require stabilization to: protect property and infrastructure such as buildings, roads and natural features; maintain sufficient setbacks for residential development; and, prevent excessive erosion and sediment transport that is detrimental to fish and fish habitat. Where multiple properties have contiguous erosion problems along their shoreline, you should try to work with other property owners to stabilize multiple properties at once to prevent causing additional erosion problems on adjacent properties. Following is a discussion on acceptable shoreline stabilization techniques that can be undertaken as part of this protocol. 3.1 Vegetative plantings Planting vegetation (bioengineering) utilizes the roots of the plants to stabilize the erodible soil. On relatively flat slopes that are not subject to regular wave or ice impacts, re-seeding or re-planting deep rooted native vegetation is often sufficient to stabilize the shoreline. This may include the use of deep-rooted grasses or sedges, shrubs, and trees. The most effective plant-based shoreline stabilization is a multi-layered strip that includes trees, shrubs, and ground covers with limited or no mowing to help minimize

3 future loss of land. It is recommended that native vegetation species such as willow, redosier dogwood or poplar be used to re-vegetate the shoreline. The highest success rate occurs when transplanting is done in late fall through early spring. Ensuring the plants have plenty of water until they are well established is also important. Vegetation planting is a good long term stabilization strategy that works well in conjunction with other techniques such as rock rip rap to provide a more natural looking shoreline. 3.2 Rock rip rap The most common type of stabilization used on Saskatchewan shorelines is rock rip rap (Figure 1). Rock rip rap is typically a mixture of cobbles and boulders placed on top of a geotextile fabric and/or granular filter layer on a stable slope [i.e., 2:1 or 3:1 (horizontal:vertical)]. The geotextile fabric/granular layers help prevent erosion beneath the rocks and keep the slope intact. Fieldstone can be used and is usually the least expensive option; however, commercial rock may also be available for a more uniform look. Rock size should be appropriate to the amount of wind wave and ice action that may be expected at your location. For example, rock with an average diameter of 30 cm (1 ) with a range of both smaller and larger sizes to fill in gaps is often effective. This allows for hand placement which is beneficial where access is restricted or when trying to prevent machine damage to the shoreline. It is important to remember that rocks may not be taken from below the OHWM of any fish bearing water and must be clean before placing on the shoreline. The rock rip rap should follow the contour of the natural shoreline and be tapered into the shoreline of the adjoining properties to avoid future erosion around the ends. Figure 1: Schematic drawing of rock rip rap.

4 Figures 2 and 3: Rock rip rap immediately after installation (left) and after a few years of vegetation growth (right). The general procedure to install rock rip rap armouring is as follows: Locate the OHWM of the shoreline and install silt fencing or filter fabric around this area to isolate it from the lake. The silt fencing or filter fabric may need to be in the water depending on water levels at time of construction. If working inland on a vertical eroded bank, re-grade the slope so that it is no steeper than 2:1 (horizontal:vertical). Dig a shallow trench at the base of where the rip rap armouring will be located. This is where the largest rocks will be placed to provide a strong support for the remaining rock above it. Install a layer of granular material (20 cm thick) or geotextile/landscaping fabric on the exposed slope. Silt fencing should not be used for this purpose as it is not porous enough. The fabric must extend from the footing/trench up and over the top of the re-graded slope. Make sure to overlap separate sections of the fabric by at least 20 cm. The top of the fabric should also be buried into the top of the slope so it can t slip down as rocks are placed on it. Place the rocks on the slope starting from the bottom. Once in place, add smaller materials to fill the voids and help lock the rocks together. It is recommended that the upper layer of the rip rap be backfilled with topsoil and planted with deep rooted native plants to increase both the strength of the structure and the aesthetic appeal of the armouring. 3.3 Vegetation and rip rap combination To create a more natural looking and stronger shoreline, it is highly recommended that native vegetation be incorporated into the riprap and above slope areas. This may be achieved by planting nursery raised shrubs, transplanting suitable species from stable areas on your property or by driving live stakes into the voids in the rip rap. The live stakes should be placed randomly in the rip rap, spaced about every 25 cm on center and cut off so only about 10 cm (4 ) is sticking out of the ground. As mentioned, willow, red osier dogwood and poplar are native species that work well for this purpose.

5 3.4 Retaining walls above the ordinary high water mark The use of vertical retaining walls for shoreline stabilization is not encouraged and generally not approved where they are located at or below the OHWM. However, if the slope to be stabilized is well above the OHWM, vertical retaining walls may be used but care should be taken to ensure the walls are appropriately constructed and designed to prevent deflection or failure. For excessively steep slopes or high banks DFO strongly recommends retaining the services of an experienced professional in designing retaining walls. In certain circumstances where, for example, building foundations have been built too close to the water and are threatened by shoreline erosion, the use of vertical walls may be necessary but you should contact the nearest DFO office prior to undertaking your project. 4.0 Measures to protect fish and fish habitat when stabilizing your shoreline The following mitigation measures listed below must be incorporated into your shoreline stabilization project. These mitigation measures are to be considered throughout the entire construction process to minimize impacts to the aquatic environment before, during and after your project is complete: No in-water work is to be undertaken during the Saskatchewan In-Water Closed Construction Timing Windows for your waterbody (see attached). If in-water work must occur during the closed timing window to protect property or infrastructure from imminent damage you must contact your nearest DFO office for direction prior to proceeding with your works. If work does need to be undertaken in the water, the work area must be effectively isolated from the rest of the waterbody prior to starting the project. Common techniques for isolation include installing sediment fencing or draping a sediment curtain/filter fabric over a support fence to contain any suspended sediment to the work area. If sediment fencing is used, the bottom of the fence should be weighted down so it remains in contact with the lakebed. If a sediment curtain/filter fabric is used, it should be suitable weighted down or anchored so it remains in contact with the lakebed at all times. Whatever isolation technique is selected, it must be regularly inspected and maintained as required to ensure effectiveness throughout the project. The shoreline stabilization works should attempt to follow the natural shape and contour of the shoreline to the greatest extent possible. Natural vegetation growing along the shoreline should be retained as much as possible to prevent additional erosion and strengthen the shoreline. No aquatic vegetation will be impacted during the project. Every reasonable effort must be made to minimize the duration of works taking place in the waterbody. Where possible, in-water work will be scheduled when conditions are calm and the potential for precipitation is low to minimize the potential for sediment to migrate from the site during in-water work activities and until exposed soils are stabilized.

6 All materials (e.g., gravel, cobble and rocks) used for shoreline stabilization are to be clean and free of fine sediments and contaminants. All material used for stabilizing the disturbed areas must not introduce additional sediment into fish habitat. All sand, gravel, rock/cobble used during the project will be obtained from an appropriate location that will not result in erosion of disturbed sediments into any water body. No materials are to be taken from below the OHWM of any waterbody. During construction and until a stable shoreline is re-established, effective sediment and erosion control measures must be used on disturbed areas to prevent sediment laden runoff from entering fish habitat. All debris from construction will be removed from the site upon completion of the project. Any garbage encountered on the shoreline during construction (e.g., tires, other debris, etc.) should be removed and disposed of in a landfill or other appropriate disposal site. Areas used for stockpiling construction materials or other equipment storage will be back from the edge of the waterbody and if possible, in areas which have already been disturbed or are devoid of vegetation. Where appropriate, DFO recommends the planting of deep rooted native vegetation species (e.g., willows, red osier dogwood, poplar, etc.) along the shoreline to provide greater stability to the bank and provide a more natural looking shoreline. Appropriate precautions should be taken to ensure that deleterious substances do not enter any waterbody: o Equipment operating near any fish bearing waters should be properly maintained, in sound mechanical condition and free of any fuel, oil, hydraulic fluid or coolant leaks. Cleaning, fueling and servicing of equipment should be conducted in an area from which spills or wash water will not enter fish habitat. o Any spilled materials should be cleaned up as soon as possible and disposed of in an environmentally safe manner. Spilled material should not be left where it may enter any fish habitat. Photographs should be taken of the project at various stages of completion so they are available upon request by DFO staff. If you feel that that you cannot meet the terms and conditions of document, then you are advised to contact your nearest DFO office prior to undertaking your project. This document does not authorize you to harmfully alter, disrupt or destroy fish habitat which is a violation of Section 35(1) of the federal Fisheries Act. Please note that this shoreline restoration and stabilization protocol document does not release you from the responsibility for obtaining any other approvals that may be required under federal, provincial or municipal legislation.

7 TIMING WINDOWS SASKATCHEWAN IN-WATER CLOSED CONSTRUCTION TIMING WINDOWS Restricted activity timing windows have been identified for Saskatchewan lakes, rivers and streams to protect fish during spawning and incubation periods when spawning fish, eggs and fry are vulnerable to disturbance or sediment. During these periods, no in-water or shoreline work is allowed except under site- or project-specific review and with the implementation of protective measures. Restricted activity periods are determined on a case by case basis according to the species of fish in the water body, whether those fish spawn in the spring or fall/winter, and whether the water body is located in Northern, Central, or Southern Saskatchewan. Fisheries and Oceans Canada Saskatchewan Operational Statement Version 3.0 Timing windows are just one of many measures used to protect fish and fish habitat when carrying out a work or undertaking in or around water. Be sure to follow all of the measures outlined in the Operational Statements to avoid negative impacts to fish habitat. Figure 1: Northern, Central, and Southern Saskatchewan boundaries for in-water closed construction timing windows. (Note: Central Region includes the Churchill River). How To Determine Timing Windows 1. Determine the fish species living in the water body where you wish to do work. Consult Saskatchewan Environment or your local Fisheries and Oceans Canada (DFO) office. 2. Determine if the fish living in the water body spawn in the spring or fall/winter according to Table 1. There may be one or both spawning types in any given water body. In Saskatchewan, essentially all lakes and streams contain one or more of the spring spawning fish listed, however far fewer contain fall/winter spawning fish. 3. Determine if the water body is located in Northern, Central, or Southern Saskatchewan according to Figure Use Table 2 to determine the in-water work timing restrictions according to the location of a water body (Northern, Central or Southern) and the type of fish found within (spring or fall spawners). During these periods, no in-water work (below the ordinary high water mark) is to occur without site- or projectspecific review by DFO.

8 Table 1: Common spring and fall/winter spawning fish. Spring Spawning Fish Fall/Winter Spawning Fish Arctic Grayling Rainbow Trout Brook Trout Bullhead Sauger Brown Trout Goldeye Smallmouth Bass Burbot (winter) Lake Sturgeon Suckers Cisco (Tullibee) Mooneye Walleye Lake Trout Northern Pike Yellow Perch Whitefish Table 2: Timing windows when no in-water work is to occur in order to protect spawning fish and developing eggs and fry. Location Spring Spawning Fish Fall/Winter and Spring Spawning Fish No Lake Sturgeon Lake Sturgeon present No Lake Trout Lake Trout present Northern Saskatchewan Central Saskatchewan Southern Saskatchewan May 1 July 15 May 1 July 31 October 1 July 15 Sept. 1 July 15 April 16 June 30 April 16 July 15 October 1 June 30 Sept. 15 June 30 April 1 May 31 April 1 July 15 October 1 May 31 Not Applicable FISHERIES AND OCEANS CANADA OFFICES IN SASKATCHEWAN Prince Albert Office Regina Office Fisheries and Oceans Canada Fisheries and Oceans Canada nd Street West 1804 Victoria Avenue East Prince Albert, SK S6V 8E2 Regina, SK S4N 7K3 Tel.: (306) Tel.: (306) Fax: (306) Fax: (306) Aussi disponible en français modernizing-moderniser/epmp-pmpe/index_f.asp DFO/ Her Majesty the Queen in Right of Canada 2007 This Operational Statement (Version 3.0) may be updated as required by Fisheries and Oceans Canada. It is your responsibility to use the most recent version. Please refer to the Operational Statements web site at to ensure that a more recent version has not been released.