State of the Watershed Report SUMMARY 2010 MESSAGE from the CO-CHAIRS

State of the Watershed Report SUMMARY 2010 MESSAGE FROM THE CO-CHAIRS Stephanie Palechek and I would like to extend our sincere appreciation to the many individuals and organizations that supported the State of the Oldman River Watershed Project through countless hours of in-kind work and financial support. In particular, we would like to thank Alberta Environment providing funding for the project and for the many in-kind hours of staff during the development of this report. It has been a long and enlightening process that could not have been completed without the contributions and hard work of the State of the Watershed Team members as well as the open and effective communication between the State of the Watershed Team and the AMEC Earth and Environmental team. The State of the Watershed Team consists of: !!!!! !!!!!<ul style="display: flex;"><li style="flex:1">Kent Bullock </li><li style="flex:1">Shane Petry (Co-chair) </li></ul>Stephanie Palechek (Co-chair) Jocelyne Leger Brian Hills Farrah McFadden Doug Kaupp Wendell Koning Andy Hurly Brent Paterson We also extend our appreciation to Mr. Lorne Fitch for writing an inspiring foreword that sets the basis from which we can begin to appreciate the beauty and complexity of our watershed – thank you Lorne. Finally, to the many people who participated in our indicator workshops as well as to those who reviewed the draft report, thank you for providing your insight, expertise and experience to the State of the Oldman Watershed Project it could not have been a success without you. Please enjoy. <ul style="display: flex;"><li style="flex:1">Shane Petry </li><li style="flex:1">Stephanie Palechek </li></ul>State of the Watershed Report SUMMARY 2010 Contents Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Indicators and Thresholds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Sub-basins and W a tershed Rankin g. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Mountain Sub-Basins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Foothills Sub-basins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Southern Tributaries Sub-basins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Prairie Sub-basins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Oldman River Mainstem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Recommendations and Best Management Practices . . . . . . . . . . . . . . . . . . . . . . 14 Planning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Stewardship . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Reclamation and Restoration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 1OVERVIEW The State of the Watershed report is a step towards understanding what we have, the challenges we face and how decisions we make today will affect future water users. This report provides a snapshot of the entire Oldman watershed: its current accounting and how well our watershed is working. The Oldman watershed is a large diverse land and water system in southern Alberta covering 23 000 km2 in southwestern Alberta and 2 100 km2 in Montana. It extends eastward from the forested slopes of the Rocky Mountains, through rangelands in the foothills, dryland and irrigated agricultural plains, to the prairie grasslands. The Rocky Mountains feed the headwaters of the Oldman mainstem and its tributaries (Crowsnest and Castle rivers, Willow and Pincher creeks), while the headwaters of the Belly, Waterton and St. Mary rivers rise in Montana. The watershed varies greatly, both in terms of the status of the land and water resources and impacts from human activities. In headwater Sub-basins, water quantity is adequate, quality is fair to good, and riparian ecosystems are generally healthy. However, as the Oldman River flows east, water quality deteriorates, available water supplies diminish, and there are several issues of concern. Moving from west to east, forests give way to grasslands and agricultural land uses. Cultivated agriculture is the main land use in 60% of the watershed and covers half or more of the Southern Tributaries and Prairie subbasins. Approximately 20% of the cultivated land is irrigated. Approximately 30% of the watershed has a soil erosion risk of moderate or more, most of which PRAIRIES SUB-BASINS FOOTHILLS SUB-BASINS occurs in the Prairie Sub-basins. The effect of long term climate change MOUNTAIN SUB-BASINS SOUTHERN TRIBUTARIES SUB-BBASINS Figure 1. Oldman Watershed and Sub-basins 2Actual water use is almost always less than total may increase the magnitude and frequency of drought and the proportion of precipitation that falls in the form of rain. These changes will increase the allocations. Water licence allocations and actual water use within the Oldman watershed are shown in Figure 2. The data for the Waterton, Belly and St. Mary rivers below the Belly-St. Mary Headworks and for the Oldman River at the Mouth indicate that there is potential for expansion in the Southern Tributaries Sub-basins and along the Oldman River mainstem without the requirement of additional allocations. However, the available water supply may not support additional expansion without increased deficits to instream needs and existing consumptive use projects with junior licence priorities. In contrast, the Little Bow River has high allocations, but the potential for expansion within existing allocations is low because there is little difference between the use and likelihood of wind and water erosion. With increasing population, expanding land use activities and potential change to more arid climatic conditions, more attention to erosion control and conservation measures is necessary. The riparian areas of the watershed are less healthy than riparian areas in Alberta as a whole. The least healthy areas in the watershed are in the Prairie Sub-basins and the Oldman River mainstem. Land use activities in the watershed include agriculture, forestry, mining, recreation, and oil and gas extraction and affect 60% of the land base. The Prairie and Southern Tributaries sub-basins are the most disturbed. Integrating results from the terrestrial and riparian indicators for land cover, soil erosion, riparian health and land use provides an overall ranking of “Fair” for the Oldman watershed. allocations. Nine of Alberta's 13 irrigation districts are sourced from waters of the Oldman watershed. Some of the irrigated lands extend beyond the Oldman watershed. The irrigation districts in the Oldman watershed (as well as in the Bow River watershed) have made significant gains in water-use efficiency from the Natural flows in the Oldman watershed are highly variable both geographically and from year to year. Trend analyses of natural flows (recorded natural flows at some hydrometric stations and reconstructed at others) show signs of decreasing flows, but trends are not considered to be statistically significant at any stations except those on Beaver Creek in the Foothills Sub-basins and the Little Bow River in the Prairie Sub-basins. Current (2006) Water Licence Allocation in the Oldman Watershed Irrigation - 83% Stockwater - 2% Commercial- 1% Other - 13% The waters of the Oldman watershed are highly regulated and extensively used. Water demands are generally low in the upper reaches of streams in the watershed, but increase to high levels in lower reaches of most streams. Generally, the higher the actual use is, expressed as a percentage of natural flow, the greater the potential for water supply deficits. However, several other factors come into play in a complex water resource system. For instance, storage and flow regulation can help to reduce deficits. Within the watershed, there are three major onstream storage reservoirs, Oldman River, Waterton and St. Mary reservoirs, with a total storage capacity of about 970 000 dam3. In addition, there are over 660 000 dam3 of offstream storage, some of which is located outside of the Oldman watershed. Municipal - 1% Current (2006) Water Use in the Oldman Watershed Irrigation - 91% Stockwater - 2% Commercial- 1% Other - 5% Municipal - 1% Source: SSRB Water Supply Study Figure 2: Water Licence Allocations and Actual Use in the Oldman Watershed 3combined impacts of more effective on-farm application processes, district conveyance improvements, and reduced return flows. neutral and/or decreasing trends that result in better conditions within upstream reaches, except in the Foothills and Prairie sub-basins. These two Sub-basins show poorer water quality and increasing trends for almost all indicators. The upstream reach of the Oldman River shows no trend, with variable trends downstream. Increasing trends and accordingly poorer water quality in the Oldman River mainstem are caused by higher loading from tributaries and/or from urban centres. Improving (decreasing) trends in the Mainstem are maintained as a result of lower loadings from the tributaries. Municipal use includes distributing water to homes, commercial and institutional establishments, and industrial users in cities, towns and villages. It does not include water use in hamlets, rural subdivisions or industrial complexes in rural areas. Water use records indicate that municipal use is usually highest in the summer months, primarily due to outside watering of lawns, gardens and parks. The total estimated surface and groundwater withdrawals for cities, towns and villages in the Oldman watershed was compared with Alberta and Canadian averages: in 2001 the average per capita withdrawal for the Oldman watershed was 742 litres per capita-day (L/c-d), which was Integrating the results of water quality analysis for nitrogen, phosphorus, total suspended solids (TSS) and fecal coliforms gives an overall rank of “Good” to “Fair” for the Oldman watershed. considerably higher than the Alberta (519 L/c-d) and Canadian (622 L/c-d) averages. Based on an evaluation of the combined ranking, the health of each of the Sub-basins is shown in Table 1. Overall, the water quantity of the Oldman watershed is “Fair” based on the results of analysis of flow variability, licensed allocation and actual use, as well as water use efficiencies within irrigation districts and municipalities. Overall, the health of the Oldman watershed is rated as “fair”. The Mountain Sub-basins are good, three Sub-basins are ranked fair, and the Prairie Sub-basins are ranked fair to poor. In the Foothills, Southern Tributaries, and Mainstem sub-basins, which are ranked fair, and the Prairie Sub-basins, land cover, riparian health, land use, water allocations, surface water nutrient levels are the indicators of most concern. Water quality in the Oldman watershed is defined primarily by natural conditions in the headwaters and is modified by downstream drainage and associated land-use patterns. A combination of effects from nonpoint sources (e.g., runoff from agricultural lands, pastures, etc.) and point sources (mainly related to municipal, industry, and irrigation return flows) creates additional loadings to streams in the watershed. All of these factors affect changes in concentrations of indicators, their temporal trends and loadings in different streams and their reaches. Storage, flow regulation, and water diversions are the keys to meeting current water use demands within the Oldman watershed. In one instance (Little Bow River sub-basin), diversions from outside the watershed are used to meet current demand. Overall, management actions in the watershed are required to maintain sustainability in light of potential expansion of demand (within current allocations) and potentially lower <ul style="display: flex;"><li style="flex:1">streamflow as a result of climate change. </li><li style="flex:1">The overall temporal trend pattern for all water </li></ul>quality indicators in the Oldman watershed shows Table 1: Overall State of the Watershed Ranking for all Indicators by Sub-basins Sub-Basins Indicator Southern Tributaries Oldman Watershed <ul style="display: flex;"><li style="flex:1">Mountain </li><li style="flex:1">Foothills </li><li style="flex:1">Prairie </li><li style="flex:1">Mainstem </li></ul>Terrestrial and Riparian <ul style="display: flex;"><li style="flex:1">Good </li><li style="flex:1">Good </li><li style="flex:1">Fair </li><li style="flex:1">Poor </li><li style="flex:1">Good </li></ul>Poor Fair <ul style="display: flex;"><li style="flex:1">Fair </li><li style="flex:1">Water Quantity </li></ul>Water Quality Overall Good Good Good Fair Fair Fair Poor Fair Fair <ul style="display: flex;"><li style="flex:1">Fair </li><li style="flex:1">Poor </li></ul>Poor Poor Fair Fair Good Fair <ul style="display: flex;"><li style="flex:1">Fair </li><li style="flex:1">Good </li></ul>Fair Fair 4managers and the public about the condition of a watershed compared to desired goals, and to help assess whether or not management actions are effective. As a result of the long history of monitoring water quantity and quality in the watershed, a large data set on indicators is available. These data provide APPROACH To assess the state of the Oldman watershed, it was divided using natural drainage patterns and water management history. Four Sub-basins – the Mountain, Foothills, Southern Tributaries, and Prairie – were defined. A fifth – the Oldman River Mainstem – was also identified because it receives and is influenced by water from the other Sub-basins (Figure 1). the opportunity to conduct an analytical assessment of indicators. For the Oldman watershed, three groups of indicators were chosen and assessed (Table 2). Indicators and Thresholds Sub-basins and Watershed Ranking In the same way performance measures show how well systems function over time, environmental indicators are used to measure the state of the watershed. Indicators allow us to understand the cause and effect relationship between human activities on the landscape and the environmental response to those activities. Indicators have three roles: to show trends in environmental conditions over time, to inform The health of each of the Sub-basins was evaluated by integrating the rankings for terrestrial and riparian ecology, water quantity, and water quality indicators to determine an overall value. A comparative assessment of the rankings assigned to each of the Sub-basins was then used to assess the overall health of the Oldman watershed. Instream Objectives (IOs) and Water Conservation Objectives (WCOs) IOs - flows that should remain in the river to protect environmental values, human uses or parts thereof. IOs are maintained through dam operations or by restrictions on licences. IOs are in place throughout the South Saskatchewan River Basin (SSRB), although some offer only limited protection of the aquatic environment. IOs have usually been set in response to fish habitat instream needs and/or water quality. WCOs are defined in Alberta's Water Act. A WCO is the amount and quantity of water necessary for the protection of a natural water body or its aquatic environment, or any part thereof. It may also include water necessary to maintain a rate of flow or water level requirements for human instream use. WCOs were established in the Oldman River Basin following completion and government approval of the SSRB plan. 5Table 2: Indicators and Thresholds used for the Oldman River State of the Watershed Report <ul style="display: flex;"><li style="flex:1">Indicator </li><li style="flex:1">Threshold </li></ul>Terrestrial and Riparian Ecology Land Cover ···Good: >50% combined land cover of forest, grassland, shrubland and rock/barren land Fair: 25 to 50% combined land cover of forest, grassland, shrubland and rock/barren land Poor: <25% combined land cover of forest, grassland, shrubland and rock/barren land Soil Erosion Rates Riparian Health ···Good: <25% of area at risk of erosion Fair: 25 to 50% of area at risk of erosion Poor: >50% of area at risk of erosion ···Good: riparian class healthy Fair: healthy but with problems Poor: unhealthy Land use ···Good: linear disturbance <2% Fair: 2 to 3% linear disturbance Poor: >3% linear disturbance Linear Developments ···Good: <50% total land use disturbance Fair: 50 to 90% total land use disturbance Poor: >90% total land use disturbance Total Land Use Disturbance Water Quantity <ul style="display: flex;"><li style="flex:1">Trends in Natural Flow </li><li style="flex:1">Thresholds for assessing water quantity within the Oldman </li></ul>watershed have not been established. Water quantity thresholds were assessed by a relative comparison among stations for each of the Sub-basins with assignment of rankings of good, fair or poor. Licensed Allocation and Actual Use vs Natural Flow Performance in Meeting IO and WCO in Recent Years Irrigation and Municipal Water Use Efficiency See above See above See above Water Quality: Nutrients - nitrogen ···Good: no exceedances or less than 10% within the data set and neutral or decreasing trends in concentration particularly over the last decade Fair: the number of exceedances not more than 50% of the analyzed data set with increasing trends in concentration for one or two indicators Poor: exceedances occur in more than 50% cases and increasing trend in concentration pronounced in more than two indicators Nutrients - phosphorus Total Suspended Solids (TSS) Fecal Coliforms See above See above See above 6average 0.3% per year at Frank and by 0.5% per year near Lundbreck. However, these annual decreases do not represent statistically significant trends. On a monthly basis, a significant decrease in flows is observed in April on the Crowsnest River. MOUNTAIN SUB-BASINS This is the westernmost portion of the Oldman watershed. The headwaters of the Crowsnest, Castle and Oldman rivers are deeply incised, narrow and swift flowing with boulders and cobbles forming the stream beds. These coldwater rivers are worldrenowned among avid anglers for their native populations of mountain whitefish and trout. In the Mountain Sub-basins, water is used for agricultural, municipal, commercial, industrial, and other uses. The largest allocation and withdrawal is for the commercial sector, primarily the Allison Creek Fish Brood Station and Hatchery west of Coleman. The hatchery has high return flows. Actual use is much less than allocations within the Mountain Sub-basins. The rivers perform better at meeting water conservation and instream objectives at downstream sites than at upstream locations, however, deficits occurred at all monitored sites, primarily during the winter low flow period. Water quantity indicators are rated as Good. The dominant land cover is forest, and activities such as forest harvesting and reforestation, grazing, fire and mountain pine beetle can all affect the watershed. The growing season is short, the climate is harsh, and wind is a constant element. Soil erosion is generally not a concern, because 87% of the Mountain Sub-basins is covered by forest and grassland. The Mountain Sub-basins riparian areas are healthier than the average in the Oldman watershed. Approximately 25% of the Mountain Sub-basins is altered by human development, with the greatest disturbance by agriculture (22%), which is concentrated in the Crowsnest River valley bottom. Extensive random recreational use (hunting, fishing, camping and OHVs) occurs throughout the Sub-basins, but data are not available to quantify the area affected. Terrestrial and riparian indicators are rated as Good. Water quality within the Mountain Sub-basins is generally within guidelines. Exceedances observed in the past are related to an extreme rainfall event in June 2005 with subsequent flooding which is reflected in high loadings for phosphorus, nitrogen, TSS, and fecal coliforms. Loadings of total nitrogen, TSS and fecal coliforms were all typically higher in the Castle River sub-basin than the Crowsnest River sub-basin. Water quality tended to improve over time at the mouth of the Crowsnest River; improvements in water quality are apparent in the Castle River for nitrogen, The Crowsnest and Castle river sub-basins have considerable snowpack and high amounts of precipitation contributing to flows typical of a mountain stream. In both rivers, recorded flows are equivalent to natural flows because the rivers are unregulated and have low water demands. Annual flows on the Crowsnest River are decreasing by an phosphorus, and fecal coliforms. Water quality indicators are rated as Good. Overall, the Mountain Sub-basins are rated as Good. 740% of the total area. This includes 1% of the land that is occupied by the Oldman, Chain Lakes and Pine Coulee reservoirs. Terrestrial and riparian indicators are rated as Good. FOOTHILLS SUB-BASINS The Foothills Sub-basins lie in the transition zone between the mountains and forests to the west and the Prairie grasslands and agricultural land to the east. Three primary tributaries -Willow, Beaver and Pincher creeks – flow into the Oldman River. Although the headwaters of these tributaries are in the mountains, all three are shallow and warm up quickly in the summer. Flows on Beaver and Pincher creeks are closer to those seen on mountain steams, while flows on Willow Creek are typical of foothills region streams. The Chain Lakes Reservoir, build in 1966, regulates flows on Willow Creek as does the offstream Pine Coulee Reservoir, built in 1999. Flows on Beaver Creek show significant decreasing trends in annual natural flow and in most months, however, Willow and Pincher creeks indicate decreasing monthly trends in April, November and December. Trends in annual flows are not significant. Land cover is a mix of cultivated land and forest and native grassland. Grassland and forest covers approximately 60%. Soil erosion is rated as negligible over most (60%) of the area with small areas of moderate risk near Claresholm and south of Fort Macleod. Riparian health is slightly better than the average for the Oldman watershed and is comparable to that found throughout Alberta. Land use (agriculture, infrastructure, urban, recreation) affects

State of the Watershed Report SUMMARY 2010 MESSAGE from the CO-CHAIRS

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