Watershed Health and Water Management in the Porcupine Hills

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1 Watershed Health and Water Management in the Porcupine Hills In Alberta, our quality of life is tied to healthy and sustainable water supplies for the environment, for our communities, and for our economic well-being. Alberta s Water for Life Strategy (2003) 0.pdf identifies three goals for water: Safe, secure drinking water; Healthy aquatic ecosystems, and; Reliable, quality water supplies for a sustainable economy. A watershed is a body of land where water from rain or snow melt drains downhill into a body of water such as a stream, wetland, river, lake, or reservoir. Water management in Alberta is conducted at the watershed scale. For the purposes of management, watersheds are organized into surface water quantity, surface water quality, groundwater, riparian areas, wetlands, and headwaters. However, it is recognized that all aspects of a watershed are intrinsically interconnected and that these interconnections are often complex. Watersheds are influenced by factors of climate, geology, and vegetation. These factors regulate the way water is received, either in the form of rain or snow; control the movement and storage of water within the vegetation and soils; and influence the release of water into streams or rivers. The Porcupine Hills are located in the eastern slopes of the Rocky Mountains and are part of the Oldman River basin within the South Saskatchewan River region. More than 75 per cent of the region s water supply comes from the eastern slopes. Headwaters protection and watershed management are key priorities outlined in the South Saskatchewan Regional Plan (SSRP) to ensure both water supply and water quality. These priorities will support healthy ecosystems and human needs realized through shared stewardship. Porcupine Hills Watershed Characterization The Porcupine Hills are part of the Montane Natural Sub-region characterized by a transition zone between grasslands to forest. Most of the Porcupine Hills were not subjected to the massive forces of glaciation, making it a unique area of the province. Geology of the area is primarily composed of mudstones and sandstone. Surface geology is composed of glaciofluvial deposits: materials from glaciers sorted and deposited by streams flowing from the melting ice. Soils in the Porcupine Hills are primarily well drained, composed of clay loams or sandy/silty clay loams of Chernozemic and Brunisolic soil classes. Areas of finer textured soils (e.g., silts and clays) are often found in the river valleys and areas where the slope changes from steep to shallow. Fine soils combined with steep slopes results in areas within the Porcupine Hills that are more sensitive to erosion and pose greater risk to stream sedimentation and water quality. 1

2 Figure 1: Average monthly air temperature and precipitation in the Porcupine hills The southern range of the eastern slopes has relatively dry summers and frequent Chinook winds during the winter that can, for periods of time, create snow-free conditions. The highest rainfall typically occurs in May and June from large, lowpressure weather systems off the Pacific Ocean and sometimes warm, moist air from the Gulf of Mexico. During July, August and September, precipitation is more often from localized systems. On average, 75 per cent of the precipitation is rainfall with the rest falling as snow. The Porcupine Hills experience large variations in precipitation year-to-year, though on average they receive 450mm and 500mm of precipitation annually. Up to 85 per cent of this precipitation is lost to the atmosphere through evapotranspiration (evaporation and transpiration from plants). The remaining 15 per cent either runs off the landscape and enters surface streamflow or contributes to sub-surface groundwater storage. Streamflow records show that almost all of the annual flow volume for the Porcupine Hills occurs between March and October with peak flows in May and June. Very low flows occur during the late fall and winter and most streams are maintained only by groundwater/spring inputs. Beneath the Porcupine Hills are layers of aquifer formations. Aquifer formations are underground layers of porous materials that contain water. The pore spaces in aquifers are interconnected so water can move through them. Under the Porcupine Hills are the Porcupine Hills formation aquifers and those of the Alberta Group. These aquifers are connected with the Willow Creek formation to the east, forming a longer, regional system connected to surface water in Trout and Willow Creeks further down in the watershed. The Porcupine Hills and Willow Creek aquifers are primarily 2

3 sandstone or shale/mudstone with relative low water yields. These aquifers are recharged by precipitation and the springs that come from them are important for maintaining winter stream flows. Streams, aquifers and springs provide important downstream water supply for human uses. Agricultural use, primarily for livestock watering, is the predominant surface water use in the Porcupine Hills. Wells use water from either aquifers or, if located near a stream, from the sub-surface flow. Challenges Aquatic areas have long been recognized for the ecosystem services they provide to people. They contribute to resiliency to drought and flood conditions, water purification, groundwater recharge and recreational opportunities, and they are centres of high biodiversity. Though streams in the Porcupine Hills are relatively small, they are an important source of water for ecosystems and human use within the Oldman River basin. Their small size makes them particularly sensitive to changes in flow, erosion and sediment increases which can negatively impact the aquatic environment (including species at risk such as Westslope Cutthroat Trout) and the suitability of the water for human use. There are several challenges to watershed health and water management in the Porcupine Hills. These include: linear disturbance, water supply and demand, the effects of climate change as well as an increase in human activity. Streams, aquifers, wetlands, and riparian areas are all sensitive to linear features such as trails, roads, and cut lines, as well as recreational activities. This is particularly true for the Porcupine Hills. Trails and roads represent a significant threat to watershed integrity as these features can be an avenue for invasive plant species; the interception of surface runoff causing a shift in the flow regime; increased erosion of soils; and increased sedimentation of streams. Ensuring enough water to meet demand can be a significant challenge. Water supply depends on the amount of precipitation and when it falls, as well as human use demand. Supporting climate change research and planning; preparing drought and flood management responses; encouraging best management practices and technology for water conservation are all essential to ensure that the region is resilient and can adapt to changing conditions over time. Water Management Quantity The Approved Water Management Plan for the South Saskatchewan River Basin continues to provide important guidance for water supply management in the region. It establishes the limit of the water resource for the Bow, Oldman and South Saskatchewan River sub-basins; recommends an interim limit of the water resource for the Red Deer River sub-basin; and establishes water conservation objectives for instream flows. An objective of the SSRP is that water is to be used as efficiently as possible to meet the current and future human and ecosystem needs. Efficient use of water is an important underlying principle everywhere, but it is 3

4 especially important in southern Alberta. One of the ways to do this is to continue to monitor and develop approaches to address the climate variability found within the South Saskatchewan River region, for both current and projected changes. Streamflow originating in the Porcupine Hills is monitored by gauges on Beaver, Meadow, Trout, and Willow creeks. Though the gauges are located downstream of the Porcupine Hills Forest Reserve they provide important monitoring information. They show that on average the mean annual combined streamflow for these creeks represents approximately 1 per cent of the entire annual streamflow of the Oldman River watershed. From 1971 to 2000, streamflow data analysis indicated that there has been a slight decline in annual streamflow for these creeks. This supports reporting from the Oldman Watershed Council which found declining trends in annual streamflows for Willow Creek and Beaver Creek from 1912 to Water Management Quality Water quality is managed based on the South Saskatchewan Region Surface Water Quality Management Framework (2014) SurfaceWaterQuality-Jul pdf. The framework will be implemented on the main stems of the South Saskatchewan River to add to and complement the existing provincial policies, legislation and regulations, and management tools. If monitoring indicates that a trigger or limit has been exceeded, there will be a management response. The framework describes the kinds of management responses that may be required, such as preparation of management plans (individual or collective), further modeling and/or monitoring, development and use of best management practices, and education and awareness programs. Management responses provide opportunities for collaborative work with governments and stakeholders in the region to find options and solutions. Water quality is influenced by land features, water uses, and both point and non-point sources. Generally, point sources are key considerations for water quality management in southern Alberta. Though the emphasis has been on ensuring effective regulation of point source discharges, non-point sources are now being examined more closely. Understanding and managing non-point sources using a combination of both nonregulatory and regulatory tools will be important to achieving water quality objectives in the region. Water quality samples collected at two locations on Beaver Creek within the Porcupine Hills Forest Reserve by the Beaver Creek Watershed Group from 2003 to 2006 indicated that water quality is good most of the time. However, during periods of high runoff caused by snowmelt or heavy rain, high levels of total suspended solids and fecal coliforms occasionally exceed guidelines for contact recreation. Most of the water quality data for the Porcupine Hills is gathered outside of the Forest Reserve and is focused on the influence of agricultural activities on water quality in the sub-watersheds. Reports from the Oldman 4

5 Watershed Council are similar to the findings of the Beaver Creek Watershed Group, indicating that runoff events can cause the exceedance of water quality guidelines. Groundwater Compared to surface water, groundwater is presently not a major source of water in the South Saskatchewan River region including the Porcupine Hills. However, groundwater springs are an important source of water during periods of low flows. This is particularly important in providing for fish habitat, specifically threatened native trout such as Westslope Cutthroat Trout and Bull Trout. Riparian and Wetlands Riparian areas are important as they are highly productive, species rich and resilient parts of the landscape. Under Alberta s Water for Life Strategy, the conservation and management of riparian lands is a key component to realizing the goal of healthy aquatic ecosystems. Initiatives such as the Cows and Fish program provide support and highlight the stewardship commitment and positive contributions of landowners to riparian health. Voluntary approaches, such as those identified in Stepping Back from the Water (2012) 4.pdf, provide practices intended to assist local authorities and watershed groups with policy creation, decision-making and watershed management relative to structural development near water bodies. The Government of Alberta has approved the Alberta Wetland Policy (2013) dpolicy-sep2013.pdf and implementation will take into consideration the regional context including past and current pressures on these areas. The Government of Alberta is also committed to increasing knowledge and mapping of wetlands, including standardizing and updating the existing wetland inventory and working with partners where appropriate. Headwaters Headwaters in the South Saskatchewan River region are managed to maintain recharge capabilities and support critical water quality, quantity, and aquatic ecosystems. The aquatic environment and the water that people in the region rely on cannot be sustained unless headwaters are protected. The Porcupine Hills form the headwaters for several sub-watersheds of the Oldman River. These include Beaver, Heath, Lyndon, Meadow, Sharples, Trout and Willow creeks, though only portions of each of these sub-watersheds are within the Forest Reserve area. Collaboration and shared stewardship will be essential to achieving responsible headwaters management. Shared Stewardship and Integrated Management Key partners for realizing Alberta s Water for Life Strategy are the Watershed Planning and Advisory Councils (WPACs) and Watershed Stewardship Groups. These partnerships bring key stakeholders together to co-create adaptive watershed management plans. Their collaborative work on watershed management plans, state of 5

6 the watershed reports, and other scientific studies has led to greater watershed awareness and improved health. There are five WPACs that have boundaries within the South Saskatchewan River region. The Porcupine Hills are within the Oldman River watershed. The WPAC for the Oldman River is the Oldman Watershed Council based out of Lethbridge. Their mission is to: improve and share knowledge; build and strengthen stakeholder partnerships; promote and facilitate community and institutional action and stewardship; and develop and implement integrated land and water plans. The Oldman Watershed Council will be an important partner in the implementation of the water objectives identified in the SSRP. It is important to continue to use collaborative approaches and to maintain and build partnerships in the region. Shared stewardship is essential. The province will continue to work with municipalities, WPACs and other stakeholders to build awareness, achieve effective watershed management, and encourage protection of water resources and responsible development. Recreation and Watershed Health There are many types of recreational activities that occur in the Porcupine Hills including hiking, mountain biking, horseback riding, and motorized Off-Highway Vehicle (OHV) use. All recreationalists should follow best practices, paying particular attention near waterbodies. There are several ways to reduce the impact of recreation activities: stay on designated trails; arrive with clean equipment (including footwear) and remove all seeds, plant matter, and mud from all equipment before leaving the area; use local or weed-free hay; and burn certified firewood. Wheeled or tracked vehicles of any type must stay out of the bed or shore of all watercourses, wetlands, or waterbodies. Crossing of a wetland, creek or river is only permitted at bridges or lawful crossings. By traveling responsibly, there can be continued access to natural areas and the preservation of these areas for the enjoyment of future generations. For more information please see: Summary The Porcupine Hills is a unique area of Alberta that provides an important source of water for aquatic ecosystems, local domestic users, agriculture, and other uses further downstream in the Oldman River watershed. The SSRP provides direction for the management of watersheds to support healthy ecosystems and human needs through by working collaboratively with local decision-makers, land managers and stakeholder groups like the Oldman Watershed Council. The South Saskatchewan Regional Plan is available at: inal%20document_ pdf. 6

7 Map of the Porcupine Hills Boundary 7