Hydrometric Data Review for 3 Sites Upstream of Okotoks, Alberta

Prepared for AMEC Foster Wheeler

05BL012 – Sheep River at Okotoks 05BL013 – Three Point Creek at Millarville 05BL014 – Sheep River at Black Diamond

Greg MacCulloch P.Eng.

6/29/2015

Acknowledgements

All data source for this review was provided by Environment Canada either through their publicly available HYDAT website (https://ec.gc.ca/rhc-wsc/default.asp?lang=En&n=894E91BE-1), the EC Data Explorer desktop application, or from personal correspondence with staff at the Water Survey of Canada, Alberta District Office in Calgary, Alberta.

The author would, in particular, like to express his gratitude to Mr. Dennis Lazowski, Hydrological Services Supervisor, WSC-Alberta for his invaluable help and generous efforts in providing the data and associated information with speed and accuracy.

Hydrometric Data Review for 3 Sites Upstream of Okotoks, Alberta

1 Introduction Subsequent to significant flooding that occurred in Southern Alberta during the month of June, 2013, a detailed look at the basic data used to compute peak flow risk is warranted. This report reviews the data provided by the National Hydrometric Program, a cost-shared program by the governments of Canada and the Provinces. It should be noted that throughout this review the terms “flowrate” and “discharge” are considered synonyms and are used interchangeably.

Factors impacting the quality of the hydrometric record used in the risk assessment include:

 Proximity to the point of interest  Length of record  Range of observation  Measurement frequency  Rating stability  Hydrograph Consistency: compare annual peak flows: Maximum Instantaneous, Maximum Daily, Event Volumes and other sites.

The preferred variable for assessing flood risk is annual maximum instantaneous peak flowrate. It is important to understand that this fundamental piece of information relied upon to derive flood risk is also a derivation, not a measurement. In general hydrometric practice, a series of direct discharge measurements are used to establish a rating curve with volumetric discharge being the dependent variable and river stage being the independent variable. Stage is the value that is commonly measured on a more or less continuous basis; except in very rare instances where stage observations are augmented by near real-time velocity data, time varying stage data is the only parameter used to derive the corresponding streamflow rates. .

The nature of streams that rise on the eastern slopes of the Canadian Rockies is such that annual peak flows are momentary in duration and often significantly larger in magnitude than the corresponding maximum daily mean flowrate, which is again often significantly larger in magnitude than the average flow for the year. Consequently, determining peak values is a challenge at best as the observational experience for such events is quite low. This is compounded further for extreme events such as those that occurred in the area in the early 1900s and again most recently in 1995, 2005, and 2013. Such extreme events create a demand for direct field observation over a large geographic area during difficult conditions. To further complicate the work the floods often cause the failure or destruction of gauging equipment at a time when accurate results are most in demand. The transitory nature of flood peaks results in an inability to revisit events to confirm results or check potential errors.

This review looks at the published hydrometric record for 3 sites at and upstream of the Town of Okotoks in the context of data suitability for high flow risk assessment. It includes a look at the basic data used for the derivation of stream flow provided by the Water Survey of Canada, Alberta District Office.

2 05BL012 – Sheep River near Okotoks

2.1.1 Proximity to point of interest: As noted in the WSC station description for this site: This station is located in the town of Okotoks. From the intersection of Hwy # 2A and Riverside Drive West, travel East for 0.7 km. The gauge is on the right side of the road, just past the intersection of Centre Ave and Riverside Drive West (also known as South Railway St). The gauge monitors flows in the largest stream to pass through the Town of Okotoks, Alberta. Any consideration of activity that might impact or be impacted by the Sheep River in the vicinity of the town should consider data from this site. Approximately 1/3 of the contributing drainage area to this point is captured at the gauging location on Threepoint Creek near Millarville, and another 1/3 is observed at the site on the Sheep River at Black Diamond.

2.1.2 Length of record Gauging has been sporadic at this site which was first established in 1908. For the 8 year period from 1908 to 1915 manual observations of stage were made during the open water season by a local observer, typically once per day (although the published record suggests less frequently as many concurrent days have the same value). From 1916 to 1920 manual observations continued on a year round basis. The operation of the gauge was discontinued for the first time after 1920.

The gauge was re-established in 1965 and operated on a continuous basis with an automatic recording device until November 30, 1968.

Continuous gauging was re-established once again in 2006 and the gauge continues to operate at the time of this review (2015); however, data computations are behind the standard and hydrometric results are only available up to December 31, 2012. Thus, peaks flows for the recent year of concern are not yet available, even on a tentative basis.

Reference to nearby gauges (Bow at Calgary, Three Point Creek near Millarville, and Sheep River at Black Diamond) indicate some significant gaps exist in the record that will impact risk analysis if the record is not extended to consider these historic events.

Notable peaks flows that are missing from the record for Sheep River at Okotoks include the years: 1915, 1916, 1923, 1929, 1970, 1990, 1995, and 2005. The last is a significant gap as peak flows for 2005 may have exceeded 2013 flows. It should be noted that for the only site in this review with data for 2013, the peak was lower than the peak for 2005.

Some significant years of low flow are missing from the record. Comparison with the same nearby sites suggests that significant years of low flow include: 1910, 1914, 1920, 1941, 1966, and the period from the late 1970s to the mid-1980s.

Any analysis of risk should consider these gaps and efforts should be made to understand how the record at this site might relate to nearby sites with more data available.

2.1.3 Range of observation: Notwithstanding the relatively short period of record, stream gaugers were successful in making a direct discharge measurement of 452 m3/s on May 27, 2011. This is close to the maximum daily peak flow of 524 m3/s measured July 16, 1915, and exceeds the highest reported daily flow of 419E m3/s May 27, 2011, (note that this is an estimated value [see table7.1.1]). In 1915 the gauge was operated manually, so there was no way to determine the value or time of the instantaneous peak. Also, an instantaneous peak for the year 2011 is not part of the hydrometric record; speculating, this was likely due to do with a gauge failure at the time of peak flow. Although a mean daily value was estimated it was likely prudent for the Water Survey of Canada technologist to be conservative and not estimate the peak.

Available record indicates that annual instantaneous peaks discharge for high flow events is in the order of a factor of 1.5 times the maximum daily mean for the year. [See 7.1.11] This is consistent with the other two sites in the review. Considering that the sum of the maximum daily flow during the 2005 high water event for Three Point Creek at Millarville[see 8.1.58], and Sheep River at Black Diamond [see 9.1.55], are close to the peak value observed in 1915 it is fair to say that the hydrometric record of observations support the results at this site. The range of direct discharge measurement can be considered good for this site, although the record length is quite short and many important flows are absent from the record due to choices made by the Hydrometric Network Administrators regarding network extent.

2.1.4 Measurement frequency Direct discharge measurements are costly; however, they are the best way to be assured of the validity of the rating curve. A review of the station visits for this site (see7.1.3] shows that apart for the month of December, the stream gauge is visited on a monthly basis and during high conditions 2 to 4 times a month. This is well within the standard for hydrometric operations.

2.1.5 Rating stability Streams in this area typically run through glaciated material making the stream beds prone to aggradation and degradation of the loosely packed sands, gravels, and cobble. The rating curve shown [see 7.1.4] includes all recent measurements; however the points subsequent to May 10, 2007 have been adjusted by adding 2.802 m to the gauge height to correspond to historic datum. Corrections such as this are common; the stage is generally referenced to an arbitrary datum plane and not linked to other references for elevation such as the Geodetic Survey of Canada.

How well individual measurements are fit to the rating curve are shown by the chart at 7.1.5 (showing the departure of the measurement from the curve by stage), and the chart at 7.1.6 (showing the same departures plotted by discharge). The charts demonstrate complete agreement with the rating when the measurements fall on the zero percent line. Negative values indicate the rating exceeds the measurement and positive values that the rating is less than the measured value. As can be seen for the gauge at Okotoks, measured values are rarely within 5% of the rating and values +- 20% are not uncommon.

It would be fair to see the same random error about the rating throughout the range of stage or flow; however, as the higher values are much less common, there is no comparison to be made. Consequently, the ratings tend to fall directly on the upper measurements giving a false confidence in the accuracy of peak events.

In this case the majority of the departures are negative suggesting that the rating may exceed an average result if many measurements were available.

To make a general statement, this rating curve should not be used by those unskilled in its application except as a guide to the shape of a rating. Accurate results for this site can only be achieved through a consistent and frequent direct discharge measurement program (as is being done) and the judicious application of shifts to the rating or stage record.

2.1.6 Hydrograph Consistency: compare Max. Inst., Max. Daily, Event Volumes and other sites. The site at Okotoks is downstream of the other two sites in this review. As these gauging locations are hydraulically and hydrologically connected it is expected that upstream responses are also observed at the downstream location. A review of the annual peak hydrographs demonstrates that this is indeed the case. Although the Calgary gauge is not hydraulically connected and the Bow River is regulated to a large degree, the patterns of highs and lows are trackable in all sites giving us confidence in the results.

3 05BL013 – Threepoint Creek near Millarville

3.1.1 Proximity to point of interest: The gauge is located in a rural area at a major road crossing. A bridge immediately upstream of the gauge may restrict flows during times of high flow; however, the hydraulic control downstream of the gauge will not be significantly altered from the natural state. The gauge monitors flows in a rural area in the foothills of a stream that is a major tributary to the Sheep River upstream of the Town of Okotoks. It is located about 10 km upstream of Threepoint Creek’s confluence with the Sheep River and about 30 km upstream of the town of Okotoks.

3.1.2 Length of record Of the three sites in the review Threepoint Creek has the longest period of record, although not significantly different from Sheep at Black Diamond. In total the gauge has been operated for 60 years over a span of 108 years, beginning in 1908 and continues today. The gauge is operated seasonally from March to October, typical of rural monitoring in Alberta. Although it lacks continuity, the summer season data is still valid for consideration of flood and drought risk. Looking at the annual extremes summarized in Table 8.1.1,early season (Feb/March) low flows are less than 100 l/s (0.1 m3/s), while maximum daily values range from a low of 3.18 m3/s in 1988 to a high of 229 m3/s in 2005.

Curiously, for the years 1966 through 1989 daily values are available yet only maximum instantaneous peak discharges are reported. The maximum daily values reported here in Table 7.1.1 were taken from the daily record available through HYDAT, the interactive archival record for Canada’s National Hydrometric Program.

This gauging site is the only one under review to present data for the 2013 year. Although 2013 is a year of interest due to the devastating flooding that occurred throughout southern Alberta, it is noteworthy that the peak flow for this site in 2013: a maximum instantaneous value of 289 m3/s is less than the maximum instantaneous value derived for the year 2005: 389 m3/s.

The summer of 2005 is an important season that needs to be considered when making a risk assessment for this area. Looking through all hydrographs for this site (7.1.13 through 7.1.34) demonstrates a pattern of multiple peaks during a short period of time. Often the series of peaks are near coincident so that one augments others in the series. In the 2005 season [see Hydrograph 8.1.58] 3 significant peaks were recorded in a span of 22 days. The maximum instantaneous value was recorded for the second peak on June 17 (229 m3/s), but the maximum daily value occurred 10 days earlier on June 7, yielding a peak of 389 m3/s. Subsequently, on June 28 a third event occurs yielding a mean daily flowrate of 140 m3/s. This value is the smallest of 3 peaks in a 22 day period, yet would have ranked 5th overall for the 60 years of record.

Traditional risk analysis looks only at the single highest value in any given year; however, it is clear from this example that such an approach may under-estimate the magnitude of extreme conditions. As the hydrographs for this site often demonstrate two or more near concurrent events that make up a peak for any year, if these 3 separate events over 3 weeks during the summer of 2005 had been closer in time a more serious flood may have occurred.

The three distinct peaks that occurred in June 2005 can be seen for many other gauging locations in the area, including Sheep River at Black Diamond, a gauge that is also subject of this review.

Reference to nearby gauges (Bow at Calgary, Sheep River at Okotoks, and Sheep River at Black Diamond) indicate some gaps exist in the record that may impact risk analysis. Notable peaks observed at nearby sites that are missing from the record for Threepoint Creek near Millarville include the years 1923 and 1929.

Some significant years of low flow are missing from the record, including1910, 1920, and 1941.

Any analysis of risk should consider the record gaps and efforts should be made to understand how the record at this site might relate to nearby sites with a longer record available.

3.1.3 Range of observation: The highest historical direct discharge measurement on record occurred May 30, 1967 when 283 m3/s was gauged at this site. Reference to gauge height is no longer relevant so this number is of little use in establishing a rating except to suggest a range and general shape of the rating curve.

The highest direct discharge measurement in recent times was 201 m3/s, June 28, 2005. The record shows 5 measurements between 150 m3/s and 200 m3/s suggesting that the rating is well supported by direct observations in that range. Of the 249 measurements available electronically since 1994, 234 of these are less than 50 m3/s.

In the context of the derived maximum instantaneous peak of 389 m3/s, the peak measurement of 201 m3/s is marginally low to establish confidence in the rating. That said, typically peaks in the foothills region occur during flood events over a wide area at all times of the day and night and are of short duration. Annual flood durations range from 2 to 12 days with the median duration being 7 days. It is difficult to establish a measurement in the range of half an instantaneous peak. The difference between observation and derivation of approximately 100% is cause for concern in any risk assessment. However, it is commendable that a high measurement in a small channel was completed at all.

Available records indicate that annual instantaneous peak discharge for high flow events is in the order of a factor of 1.5 times the maximum daily mean for the year [See 8.1.11]. This is consistent with the other sites in the review.

Understanding that peak flow determination without supporting direct discharge measurement is problematic, it would be of benefit to support the peak flow determination by indirect means (e.g., 6

slope- area measurement conducted after the fact); nevertheless having a measurement (200 m3/s ) that is 70% of the maximum daily value (229 m3/s) is very good. However, flood risk is generally considered using maximum instantaneous values, and in this case the highest measurement (200 m3/s) is only 51% of the peak (389 m3/s). Further, the standard field practice of demonstrating consistency by repeating any measurement that results in a total discharge that is more than 10% off the rating curve (always the case for unknown peaks values during flood events) is rarely done in practice (certainly not demonstrated for any of the 3 gauges in this review). During a flood event, the hydrographer must balance the demands form streamflow forecasters to collect data from as many sites as possible rather than making double measurements to satisfy rating curve development criteria. As is appropriate, concern over lives and property risk trumps science concerns when floods are happening.

The range of direct discharge measurement can be considered good for this site; however, the uncertainty of peak flow determination should be taken into consideration when determining flood risk.

3.1.4 Measurement frequency A review of the station visits for this site [see 8.1.3] demonstrates that the stream gauge is visited on a monthly basis and during high conditions 2 to 4 times a month. This is well within the standard for hydrometric operations.

3.1.5 Rating stability Streams in this area typically run through glaciated material making the stream beds prone to aggradation and degradation of the loosely packed sands, gravels, and cobble. The rating curve shown [see 8.1.4] includes all recent measurements. Looking at the available measurement data (i.e., since 1994), results prior to the 2005 high water event do not relate to current conditions. This could be due to a variety of factors including changes to the channel by natural means, highway and bridge construction, or by loss of original reference points due to bank erosion and the consequent need to establish a new gauge datum.

There is no sense speculating on the cause for the change in datum as there are sufficient measurements to show a stable rating between 2005 and 2012. As mentioned above there is some concern that the magnitude of the highest measurement is only half the peak determined from this curve, but we have some confidence that the general shape of the high curve is more or less parallel to high measurements observed at this site in 1967.

How well individual measurements are fit to the curve are shown by chart 8.1.5 showing the departure of the measurement from the curve by stage, and chart 8.1.6 showing the same departures plotted by discharge. The charts demonstrate complete agreement with the rating when the measurements fall on the zero percent line. Negative values occur when the rating exceeds the measurement and positive values occur when the rating is less than the measured value. As can be seen on the charts 8.1.5 and 8.1.6, the gauge near Millarville of the 70 values plotted only 7 are within +-5% of the rating curve. Measured values for this gauge are rarely within 5% of the rating and values +- 20% are not uncommon.

It is expected that some systematic errors are at play to explain some of the large departures of measurements from the rating curves. If the differences are due to random error, it would be fair to see the same random error about the rating throughout the range of stage or flow; however, as the higher values are much rarer, there is no comparison to be made. The lack of experience at peak flowrates for a rating curve generally leads to the common approach of forcing the rating through the few peak values that are available giving a false confidence in the accuracy of peak events.

In the case of Threepoint Creek near Millarville, for flows exceeding 5 m3/s up to 50 m3/s it appears equally likely that the rating and the measurement to disagree by as much as 50%. For values higher than 50 m3/s there is not enough information to make a valid judgement.

As is the case for many hydrometric sites, this rating curve should not be used except as a general guide to the shape of a rating by experienced practitioners. Accurate results for this site can only be achieved through a consistent and frequent direct discharge measurement program (as is being done) and the judicious application of shifts to the rating or stage record.

3.1.6 Hydrograph Consistency: compare Max. Inst., Max. Daily, Event Volumes and other sites. The site near Millarville is the most upstream of the three sites in this review. All three gauging locations are hydraulically and hydrologically connected so it is expected that upstream responses are also observed at the downstream location. A review of the annual peak hydrographs demonstrates that this is indeed the case. Although the Calgary gauge is not hydraulically connect and is regulated to a large degree, the patterns of highs and lows are trackable in all sites giving us confidence in the results.

4 05BL014 – Sheep River at Black Diamond

4.1.1 Proximity to point of interest: The gauge is located on the floodplain downstream of a major highway bridge at the town of Black Diamond, Alberta. The watershed to this point is predominately rural ranging from alpine to foothills to rolling prairie, much like the watershed leading to the gauge near Millarville. The highway bridge is large and robust and would not likely restrict flow except during the most extreme conditions. The contributing drainage area to this location is about 1/3 of the drainage to the Town of Okotoks. Another 1/3 contributes to the gauge location on Threepoint Creek near Millarville. The gauge is located about 10 km upstream of the confluence with the Threepoint Creek and 25 km upstream of the town of Okotoks. Any considerations of the impact of the communities upstream of Okotoks on the rivers, or the impact of waterways on infrastructure in the vicinity of Okotoks, should utilize data from this site.

4.1.2 Length of record Gauging for Station 05BL014 began in 1908 as Sheep River at Turner Valley. Records at the WSC District Office in Calgary describe the original location as 1 km west of Black Diamond. The station was moved and renamed under the same station number approximately 3 km downstream in October 1981. In 1997 the datum was lowered by 1 meter. The gauge was destroyed during the 2013 flooding and relocated below the highway bridge, approximately 100 m downstream of its previous location.

In the 108 intervening years since gauging was first established in the vicinity of the Town of Black Diamond, the gauges have been operated for 57 years with the longest contiguous period of record being from 1968 to present (2015). At the time of this review, only data to 2012 is computed and available: a 45 year period. A summary of station information and data collection history can be found at 6.3.1.

The same effect of 3 significant peaks during the summer of 2005 for Threepoint Creek is also observed in the data for the Sheep River at Black Diamond and is worthy of special note. These 3 events are significant and need to be considered specifically when making a risk assessment for this area. Looking through all hydrographs for the station demonstrates a pattern of multiple peaks during a short period of time and often the events are near coincident so that one peak augments the other. In the 2005 season [see Hydrograph 9.1.55], 3 significant peaks were recorded in a span of 22 days. The maximum instantaneous value for the second peak was computed for June 17 (380 m3/s), but the maximum daily value determined to occur 10 days earlier on June 7 yielding a peak of 245 m3/s. Subsequently, on June 28 a third event yielded a mean daily flowrate of 118 m3/s. This value is the smallest of 3 peaks in a 22 day period, yet it would have ranked 11th overall for the 57 years of record.

As for the station Threepoint Creek near Millarville, if these events had occurred closer in time so as to compound each other there exists the potential for much more serious flood. 9

Reference to nearby gauges (Bow at Calgary, Sheep River at Okotoks, and Threepoint Creek near Millarville) indicate some gaps exist in the record that may impact risk analysis. Notable peaks that have been recorded elsewhere yet are missing from this site include 1923, 1929 and 1932. Further, the year 1993 has a significant maximum daily flow but the corresponding maximum instantaneous value for that year is missing from the record.

Also, some significant years of low flow are missing from the record. Comparing the same nearby sites suggest that significant years of low flow include 1910, 1920, and 1941.

Any analysis of risk should consider the record gaps and efforts should be made to understand how the record at this site might relate to other nearby sites with a longer record available.

4.1.3 Range of observation: The highest historical direct discharge measurement available electronically (i.e., since 1994) occurred June 7, 2005 when 277 m3/s was gauged at this site (see Table 9.1.2). Comparing this to the reported maximum annual instantaneous peak of 380 m3/s June 17, 2005 [see Table 9.1.1] it can be easily calculated that the highest measurement is 73% of the peak value(note 2012 was last year available at the time of this review). This is a reasonable departure from a peak for the flashy streams that rise on the eastern slopes.

As for most eastern slopes streams, the majority of the measurements are during low flow conditions. Of the measurements taken since 1994, 62.9% (185 measurements) occur for discharge quantities less than 1% of the peaks discharge reported (i.e., less than 3.8 m3/s). Further, 40.8% (120 measurements) are less than 0.5% of the reported peak.

The fact that there is so little experience at the higher flow rates needs to be understood when assessing flood risk. The top 10 measurements have the following magnitudes in m3/s: 277, 173, 154, 146, 96.4, 95.5, 84.3, 78.3, 72.2, and 66.8. Comparing these to the list of top 10 annual peak discharges (also in m3/s): 380, 366, 259, 207, 195, 185, 185, 150, 126, and 121 demonstrates that the range of flows is well covered; however, there are only single observations during the extreme high flow events. Therefore, the only corroborating evidence of validity of a singular events relating to a rating is the degree of linearity among the elements in the series. Looking at the measurements as plotted against the rating curve [see 9.1.4] suggests good linearity above a stage of 2.5 meters. Looking at the same information plotted as departures from the curve [see 9.1.15 and 9.1.6] indicates that although the range in stage is well covered, departures from the rating are almost all greater than +- 5% with many being +- 50% or greater.

4.1.4 Measurement frequency A review of the station visits for this site (see 9.1.3] demonstrates that the stream gauge is visited on a monthly basis and during high conditions 2 to 4 times a month. This is well within the standard for hydrometric operations.

4.1.5 Rating stability Streams in this area typically run through glaciated material making the stream beds prone to aggradation and degradation of the loosely packed sands, gravels, and cobble. The rating curve shown [see 9.1.4] includes all recent measurements. Measurements prior to 1997 have been adjusted by 1 m to accommodate the change made to the datum in 1997.

Measurements plotted on the rating curve show good agreement with the general shape of the curve. However apart from the highest measurements, for which there is scant experience, the individual measurements around the curve vary widely, in particular for flows less than 100 m3/s or stages below 2.5 m. Of the 294 measurements available for review, only 4 measurements have been made above 2.5 m in stage and no check measurements have been possible to validate the curve.

How well individual measurements are fit to the curve are shown by the Chart 9.1.5 showing the departure of the measurement from the curve by stage, and Chart 9.1.6 showing the same departures plotted by discharge. The charts demonstrate complete agreement with the rating when the measurements fall on the zero percent line. Negative values are when the rating exceeds the measurement and positive values are when the rating is less than the measured value. As can be seen on the charts, of the 63 values plotted only 9 are within +-5% of the rating curve. For this site, measured values are rarely within 5% of the rating and values greater than +- 30% are not uncommon.

It would be reasonable to see the same random error about the rating throughout the range of stage or flow; however, at high values of stage it is rare to find two proximal measurements for which a comparison can be made. It is not likely that measurements made during high flow should demonstrate less scatter about the mean than measurements made at lower flowrates. In hydrometric determinations some systematic error exists in all measurements, the degree of which is not understood for this site. As is the case for most gauge locations, the lack of experience at peak flowrates for a rating curve generally leads to the common approach of forcing the rating through the few peak values that are available giving a false confidence in the accuracy of peak events. If we consider that the discharge measurements at the top end of the rating curve are much more difficult to measure and subject to rapidly changing conditions, it is likely that peak flows determined by hydrograph extension are subject to large errors.

As is the case for many hydrometric sites, this rating curve should not be used except as a general guide to the shape of a rating by experienced practitioners. Accurate results for this site can only be achieved through a consistent and frequent direct discharge measurement program and the judicious application of shifts to the rating or stage record.

4.1.6 Hydrograph Consistency: compare Max. Inst., Max. Daily, Event Volumes and other sites. The site at Black Diamond has a relatively long period of record and although the gauge has often been damaged and failed to work during the most extreme flooding, it has been operated through some of

the most serious high water events in the last 100 years. Such longevity makes this site very important as a reference for hydrology in the vicinity of the Town of Okotoks.

Comparing this site to nearby locations demonstrates no obvious abnormalities.

5 Conclusions This review observes good consistency among the sites. This is to be expected as hydrometric records are rarely produced independently and comparison between sites is part of the process applied in the derivation of streamflow from stage data.

In terms of suitability to task of this information for high flow risk assessment proximal to the Town of Okotoks the following generalizations can be made:

1. All 3 sites should be used in any decision making on the risk of high flow occurrences. 2. The record for the two upstream sites includes some significant and recent high flow events, making these sites most valuable in the risk assessment. 3. It is known that the peak flows for the 2013 year are significant and important in the assessment of risk for this area. At a minimum the peak flows for the 2013 year should be obtained prior to the assessment of flood risk. 4. Rating curves should not be employed without an understanding of the data used in their derivation. In general, accurate results are dependent on a consistent and frequent direct discharge measurement program and the judicious applications of shifts to the rating or stage record. The frequency of station visits suggests that this is well understood and is being done by the Water Survey of Canada. 5. Caution should be employed in application of derived peak flowrates. The review of rating curve stability indicates significant variability at low flows and the fact that opportunities for high flow measurements are rare makes it difficult to establish accurate ratings curves by direct discharge measurements alone 6. Although not specifically germane to the context of this review, efforts should be made to influence the National Hydrometric Program Partners (Province of Alberta and Government of Canada) to work towards peak flow validations for gauge locations on the eastern slopes of the Rocky Mountains. Techniques such as double measuring when results are more than 10% off the rating curve, post-facto determination of peak flow by indirect means, flood routing with HEC- RAS, etc. are well established and should be considered as fundamental to peak flow determination. 7. Special attention should be made to the 2005 summer season. At the only site for which 2013 data is available, peak flows for 2005 were higher than the peak derived for 2013. More importantly, 3 peaks occurred in 22 days during 2005, each of which could have been in the top 10 occurrences for the gauge sites. As the hydrographs demonstrate that annual peaks are commonly the result of the superposition of one or more peaks, the risk of flows similar to 2005 occurring in closer proximity resulting in compounding flows should be considered in the analysis of risk.

6 Station Record Summary

6.1 SHEEP RIVER AT OKOTOKS (05BL012) [AB]

6.1.1 Station Information No table of figures entries found.

Active or discontinued: Active Regulation length: N/A

Province / Territory: Alberta Real-time data available: Yes

Latitude: 50° 43' 26'' N Sediment data available: Yes

Longitude: 113° 58' 24'' W Type of water body: River

Gross drainage area: 1493.9 km2 Reference Site (RHBN): No

Effective drainage area: N/A EC Regional Office: CALGARY

Record length: 27 Years Data contributed by: N/A

Period of record 1908 - 2015 Datum of published data: ASSUMED DATUM Regulation type: Natural

6.1.2 Data Collection History

Period of Type Operation Gauge type operation schedule

1908 - 1915 Flow Seasonal Manual

1916 - 1920 Flow Continuous Manual

1965 - 1968 Flow Continuous Recorder

2006 - 2011 Flow Continuous Recorder

2012 - 2015 Flow & Continuous Recorder Level Date modified: 2015-03-06

6.2 THREEPOINT CREEK NEAR MILLARVILLE (05BL013) [AB]

6.2.1 Station Information Active or discontinued: Active Real-time data available: Yes

Province / Territory: Alberta Sediment data available: Yes

Latitude: 50° 46' 16'' N Type of water body: River

Longitude: 114° 16' 43'' W Reference Site (RHBN): No

Gross drainage area: 507.2 km2 EC Regional Office: CALGARY

Effective drainage area: N/A Data contributed by: N/A

Record length: 60 Years Datum of published data: ASSUMED DATUM Period of record 1908 - 2015 To convert to APPROXIMATE GEODETIC Regulation type: Natural SURVEY OF CANADA DATUM, add 1155 m

Regulation length: N/A

6.2.2 Data Collection History

Period of Type Operation Gauge type operation schedule

1908 - 1911 Flow Miscellaneous Manual

1912 - 1916 Flow Seasonal Manual

1965 - 2011 Flow Seasonal Recorder

2012 - 2015 Flow & Seasonal Recorder Level Date modified: 2015-03-06

6.3 SHEEP RIVER AT BLACK DIAMOND (05BL014) [AB]

6.3.1 Station Information Active or discontinued: Active Regulation length: N/A

Province / Territory: Alberta Real-time data available: Yes

Latitude: 50° 41' 16'' N Sediment data available: Yes

Longitude: 114° 14' 37'' W Type of water body: River

Gross drainage area: 592.2 km2 Reference Site (RHBN): No

Effective drainage area: N/A EC Regional Office: CALGARY

Record length: 57 Years Data contributed by: N/A

Period of record: 1908 - 2015 Datum of published data: ASSUMED DATUM Regulation type: Natural

6.3.2 Data Collection History

Period of Type Operation Gauge type operation schedule

1908 - 1908 Flow Miscellaneous Manual

1909 - 1916 Flow Seasonal Manual

1968 - 2011 Flow Continuous Recorder

2012 - 2015 Flow & Continuous Recorder Level Date modified: 2015-03-06

6.4 BOW RIVER AT CALGARY (05BH004) [AB]

6.4.1 Station Information Active or discontinued: Active Real-time data available: Yes

Province / Territory: Alberta Sediment data available: Yes

Latitude: 51° 03' 00'' N Type of water body: River

Longitude: 114° 03' 05'' W Reference Site (RHBN): No

Gross drainage area: 7868.2 km2 EC Regional Office: CALGARY

Effective drainage area: N/A Data contributed by: N/A

Record length: 115 Years Datum of published data: ASSUMED DATUM Period of record: 1896 - 2015 To convert to GEODETIC SURVEY OF Regulation type: Regulated CANADA DATUM, add 1038.03 m Regulation length: N/A 6.4.2 Data Collection History Period of operation Type Operation Gauge type schedule

1896 - 1899 Level Seasonal Manual

1900 - 1901 Level Seasonal Manual

1902 - 1902 Level Seasonal Recorder

1905 - 1905 Level Seasonal Recorder

1908 - 1909 Flow Seasonal Manual

1910 - 1913 Flow Continuous Manual

1914 - 1950 Flow Continuous Recorder

1952 - 1952 Flow Seasonal Recorder

1953 - 2011 Flow Continuous Recorder

2012 - 2015 Flow & Continuous Recorder Level Date modified: 2015-03-06 19

6.5 BOW RIVER BELOW GHOST DAM (05BE006)

6.5.1 Station Information Active or discontinued: Discontinued Regulation length: N/A

Province / Territory: Alberta Real-time data available: No

Latitude: 51° 12' 50'' N Sediment data available: No

Longitude: 114° 36' 40'' Type of water body: River

Gross drainage area: 6550 km2 Reference Site (RHBN): No

Effective drainage area: N/A EC Regional Office: CALGARY

Record length: 52 Years Data contributed by: N/A

Period of record: 1933 - 1989 Datum of published data: ASSUMED DATUM Regulation type: Regulated

6.5.2 Data Collection History

Period of Type Operation Gauge type operation schedule

1933 - 1936 Flow Seasonal Recorder

1937 - 1962 Flow Continuous Recorder

1968 - 1979 Flow Continuous Recorder

1980 - 1989 Flow Seasonal Recorder Date modified: 2015-03-06

6-20

6.6 Preliminary Review of Period of Record and Hydrographs

6.6.1 Long Term Comparison of Proximal Hydrographs

6.6.2 Period of Record Hydrograph for 05BL012- Sheep River at Okotoks

6.6.3 Period of Record Hydrograph for 05BL013- Three Point Creek at Millarville

6.6.4 Period of Record Hydrograph for 05BL014- Sheep River at Black Diamond

6.6.5 Period of Record Hydrograph for 05BH004 – Bow River at Calgary

7 05BL012-Sheep River at Okotoks

7.1.1 Summary of Peak Flow Data for 05BL012 – Sheep River at Okotoks

Daily

Annual

Flow

CODE

(m3/s) (m3/s) (m3/s)

HH:MM

SYMBOL SYMBOL SYMBOL

Occurrence (DD)

Time Zone

Mean Flow

of Occurrence (MM)

Year of Record

Daily Mean Flow

B=ice, E=Estimate B=ice, E=Estimate B=ice, E=Estimate

Time of Peak Flow

Maximum

Instantaneous Peak Instantaneous Peak

InstantaneousPeak

Minimum Daily Mean Minimum Daily Mean

Maximum Daily Mean Maximum Daily Mean

Minimum

Day of Day of Occurrence (DD) Day of Occurrence (DD)

Month of Occurrence (MM) Month of Occurrence (MM) Month 1908 218 6 2 1909 96 5 25 1910 11.6 5 26 1911 68.2 8 8 1912 154 6 16 1913 44.7 6 28 1914 24.2 6 4 1915 524 7 16 1916 265 8 18 1917 154 6 3 0.085 B 2 2 1918 24.6 6 10 0.51 B 2 19 1919 55.5 8 4 0.51 B 2 19 1966 60.9 6 5 0.283 B 12 4 1967 476 5 31 0.58 B 3 11 1968 62 6 9 2006 283 A 23:00 MST 6 15 217 A 6 16 2007 55 8:16 MST 6 18 50.9 6 18 0.625 B 2 10 28

Daily

Annual

Flow

CODE

(m3/s) (m3/s) (m3/s)

HH:MM

SYMBOL SYMBOL SYMBOL

Occurrence (DD)

Time Zone

Mean Flow

of Occurrence (MM)

Year of Record

Daily Mean Flow

B=ice, E=Estimate B=ice, E=Estimate B=ice, E=Estimate

Time of Peak Flow

Maximum

Instantaneous Peak Instantaneous Peak

InstantaneousPeak

Minimum Daily Mean Minimum Daily Mean

Maximum Daily Mean Maximum Daily Mean

Minimum

Day of Day of Occurrence (DD) Day of Occurrence (DD)

Month of Occurrence (MM) Month of Occurrence (MM) Month 2008 383 2:01 MST 5 25 274 5 25 0.65 B 1 31 2009 37.3 6:01 MST 5 31 31.8 5 31 0.8 B 2 15 2010 86.5 4:31 MST 6 18 76.2 6 18 0.75 B 2 22 2011 419 E 5 27 0.599 B 2 18 2012 267 A 6 24 0.763 B 1 1

7.1.2 Recent Direct Discharge Measurements: 05BL012 – Sheep River at Okotoks 05BL012 - SHEEP RIVER AT OKOTOKS 05BL012 - SHEEP RIVER AT OKOTOKS 05BL012 - SHEEP RIVER AT OKOTOKS

Discharge Stage Discharge Stage Discharge Stage Date Date Date (m^3/s) (m) (m^3/s) (m) (m^3/s) (m)

01/01/1980 8.359 26.218 05/11/2008 2.665 25.922 09/03/2012 1.1487 26.45 14/02/2006 1.495 23.282 08/12/2008 1.703 25.849 28/03/2012 1.5613 26.094 16/03/2006 1.408 23.26 05/01/2009 1.075 25.818 12/04/2012 2.9764 26.166 23/03/2006 1.613 23.363 02/02/2009 1.067 25.772 08/05/2012 16.896 26.55 19/04/2006 3.566 23.412 11/03/2009 0.835 25.736 06/06/2012 133.1178 27.597 30/05/2006 12.057 23.606 26/03/2009 1.882 25.867 25/06/2012 124.1354 27.353 15/06/2006 72.658 24.375 08/04/2009 3.095 25.982 31/07/2012 8.1658 26.312 16/06/2006 248.659 25.546 20/04/2009 9.94 26.407 29/08/2012 3.8535 26.152 17/06/2006 97.63 24.614 26/05/2009 24.974 26.714 02/10/2012 2.7749 26.063 21/06/2006 46.327 24.125 07/07/2009 17.365 26.554 30/10/2012 2.6167 26.066 07/07/2006 10.745 23.666 05/08/2009 33.594 26.829 26/11/2012 1.2251 25.996 12/07/2006 9.291 23.618 09/09/2009 3.015 25.947 07/01/2013 1.0639 26.153 17/08/2006 5.033 23.51 07/10/2009 2.73 25.901 05/02/2013 0.95 26.105 06/09/2006 2.586 23.411 05/11/2009 2.118 25.871 25/02/2013 1.0359 26.082 26/10/2006 3.372 23.448 09/12/2009 1.033 25.792 22/03/2013 2.0025 26.255 04/12/2006 1.599 23.608 06/01/2010 0.923 25.862 25/04/2013 3.3923 26.122 08/01/2007 1.319 23.41 03/02/2010 0.949 25.727 31/05/2013 43.5 26.939 05/02/2007 1.06 23.625 26/02/2010 0.757 25.666 24/06/2013 121.6802 27.687 26/02/2007 0.997 23.499 25/03/2010 1.021 25.704 26/06/2013 69.6909 27.228 09/03/2007 6.805 23.926 09/04/2010 1.31 25.732 22/08/2013 7.8426 26.418 30/03/2007 3.472 23.466 07/05/2010 4.03 26.038 03/10/2013 6.2151 26.363 26/04/2007 9.105 23.666 08/06/2010 26.681 26.743 25/10/2013 5.5634 26.261 10/05/2007 15.471 23.789 08/07/2010 9.546 26.261 10/12/2013 1.8322 26.207

05BL012 - SHEEP RIVER AT OKOTOKS 05BL012 - SHEEP RIVER AT OKOTOKS 05BL012 - SHEEP RIVER AT OKOTOKS

Discharge Stage Discharge Stage Discharge Stage Date Date Date (m^3/s) (m) (m^3/s) (m) (m^3/s) (m)

10/05/2007 15.471 26.591 04/08/2010 8.359 26.218 06/01/2014 2.0831 26.229 31/05/2007 22.623 26.751 10/09/2010 10.924 26.314 03/02/2014 1.7189 26.258 07/06/2007 40.669 27.039 07/10/2010 6.874 26.183 24/02/2014 1.5253 26.116 12/06/2007 19.073 26.685 28/10/2010 3.964 26.071 17/03/2014 21.574 26.802 21/06/2007 31.549 26.873 30/11/2010 2.092 26.116 24/04/2014 13.9587 26.642 20/07/2007 7.161 26.397 05/01/2011 1.327 26.126 05/06/2014 27.9742 26.883 23/08/2007 2.486 26.216 01/02/2011 0.902 26.092 20/06/2014 164.9304 27.604 13/09/2007 4.773 26.322 04/03/2011 0.921 26.168 21/06/2014 98.8862 27.247 01/11/2007 2.636 26.254 25/03/2011 1.261 26.076 02/07/2014 23.8894 26.59 10/12/2007 1.334 26.294 08/04/2011 2 26.045 07/08/2014 5.7039 26.176 07/01/2008 1.089 26.281 27/04/2011 34.122 26.7 02/09/2014 4.7248 26.158 04/02/2008 0.671 26.381 27/05/2011 451.984 28.502 06/10/2014 6.8307 26.331 03/03/2008 1.28 26.358 28/05/2011 257.583 27.923 03/11/2014 4.233 26.142 27/03/2008 1.15 26.154 31/05/2011 66.343 27.125 09/12/2014 2.8839 26.248 09/05/2008 13.3 26.527 22/06/2011 56.767 27.091 06/01/2015 2.1938 26.354 25/05/2008 251 28.159 04/08/2011 5.782 26.278 03/02/2015 2.6937 26.304 27/05/2008 99.6 27.517 24/08/2011 3.535 26.184 23/02/2015 1.4517 26.163 05/06/2008 55.323 27.19 27/10/2011 2.043 26.136 16/03/2015 4.7195 26.2 09/07/2008 11.597 26.454 28/11/2011 1.344 26.157 22/04/2015 5.8547 26.208 13/08/2008 3.835 26.05 03/01/2012 1.2297 26.185 20/05/2015 11.03 26.339 01/10/2008 4.195 26.068 30/01/2012 1.022 26.406

7.1.3 Station Visit Frequency: 05BL012 - Sheep River at Okotoks

7.1.4 Rating Curve No. 5 Showing Recent Measurements: 05BL012-- Sheep River at Okotoks

7.1.5 Measurement Departure from Rating Curve by Stage: 05BL012 – Sheep River at Okotoks

7.1.6 Measurement Departure from Rating Curve by Discharge: 05BL012 – Sheep River at Okotoks

7.1.7 Duration of Annual Flood from Peak Hydrographs: 05BL012 - Sheep River at Okotoks

7.1.8 Annual Flood Volume Vs. Annual Max. Inst Flow: 05BL012 - Sheep River at Okotoks

7.1.9 Annual Flood Volume Vs. Annual Max. Daily Flow: 05BL012 - Sheep River at Okotoks

7.1.10 Rank of Annual Extremes by Peak and by Volume: 05BL012 -Sheep River at Okotoks

7.1.11 Compare Annual Maximum Instantaneous Peak to Maximum Daily: 05BL012 Sheep River at Okotoks

7.1.12 Combined Annual Peak Hydrographs: 05BL012 – Sheep River at Okotoks

7.1.13 Sheep River at Okotoks 1908

7.1.14 Sheep River at Okotoks -1909

7.1.15 Sheep River at Okotoks - 1910

7.1.16 Sheep River at Okotoks – 1911

7.1.17 Sheep River at Okotoks – 1912

7.1.18 Sheep River at Okotoks -1913

7.1.19 Sheep River at Okotoks - 1914

7.1.20 Sheep River at Okotoks 1915

7.1.21 Sheep River at Okotoks – 2016

7.1.22 Sheep River at Okotoks - 1917

7.1.23 Sheep River at Okotoks – 1918

7.1.24 Sheep River at Okotoks – 1919

7.1.25 Sheep River at Okotoks- 1966

7.1.26 Sheep River at Okotoks - 1967

7.1.27 Sheep River at Okotoks -1968

7.1.28 Sheep River at Okotoks – 2006

7.1.29 Sheep River at Okotoks – 2007

7.1.30 Sheep River at Okotoks - 2008

7.1.31 Sheep River at Okotoks – 2009

7.1.32 Sheep River at Okotoks - 2010

7.1.33 Sheep River at Okotoks - 2011

7.1.34 Sheep River at Okotoks - 2012

8 05BL013 –Three Point Creek at Millarville

8.1.1 Summary of Peak Flow Data for 05BL013 –Three Point Creek at Millarville Note: Data for cells shaded in blue have been taken from daily record for years where the data was absent from the Peaks file in HYDAT.

(MM) (MM) (MM)

(DD) (DD) (DD)

Annual

Flow

CODE

(m3/s) (m3/s) (m3/s)

Occurrence Occurrence Occurrence

HH:MM

SYMBOL SYMBOL SYMBOL

Occurrence Occurrence Occurrence

Time Zone

Year of Record

Daily Mean Flow Daily Mean Flow

Minimum

B=ice, E=Estimate B=ice, E=Estimate B=ice, E=Estimate

Time of Peak Flow

Maximum

Instantaneous Peak Instantaneous Peak

InstantaneousPeak

Minimum Daily Mean Minimum Daily Mean

Maximum Daily Mean Maximum Daily Mean

Day of Day of Day of

Month of Month of Month of 1909 23.1 5 24 1912 25.5 7 8 1913 15.5 5 14 1914 8.01 6 14 1915 159 0:00 6 26 60 6 26 1916 47 8 18 1966 32.6 6:00 MST 6 10 24.6 6 5 1967 283 22:00 MST 5 30 164 5 31 1968 26 10:15 MST 6 8 20.2 6 8 1969 146 14:25 MST 6 29 109 6 29 1970 75.9 8:35 MST 6 14 56.1 6 14 1971 41.6 13:00 MST 6 6 30.9 6 6 1972 27.3 22:00 MST 4 6 18 4 6 1973 32.8 18:00 MST 5 26 24.6 5 27 1974 53.8 23:30 MST 4 30 34.3 4 30 1975 33.1 20:00 MST 6 20 28.9 6 20 1976 17.4 20:00 MST 8 9 13 8 10 65

(MM) (MM) (MM)

(DD) (DD) (DD)

Annual

Flow

CODE

(m3/s) (m3/s) (m3/s)

Occurrence Occurrence Occurrence

HH:MM

SYMBOL SYMBOL SYMBOL

Occurrence Occurrence Occurrence

Time Zone

Year of Record

Daily Mean Flow Daily Mean Flow

Minimum

B=ice, E=Estimate B=ice, E=Estimate B=ice, E=Estimate

Time of Peak Flow

Maximum

Instantaneous Peak Instantaneous Peak

InstantaneousPeak

Minimum Daily Mean Minimum Daily Mean

Maximum Daily Mean Maximum Daily Mean

Day of Day of Day of

Month of Month of Month of 1977 17.3 22:30 MST 4 4 7.65 4 5 1978 37.1 8:00 MST 5 31 27.3 5 31 1979 10.4 3:00 MST 4 28 9.03 5 17 1980 38.5 2:30 MST 6 4 31.7 6 4 1981 45.2 2:30 MST 6 14 34.3 6 14 1982 18.1 7:12 MST 6 28 14.3 6 30 1983 32.6 8:29 MST 4 25 21.6 4 25 1984 7.86 13:00 MST 6 9 7.12 6 9 1985 40.1 5:07 MST 9 13 33.7 9 13 1986 13 0:18 MST 9 27 11.5 5 22 1987 12.1 B 4 1 1988 3.45 10:52 MST 8 21 3.19 8 21 1989 14 23:47 MST 4 14 8.25 4 15 1990 56.3 9:15 MST 5 26 51.3 5 26 0.016 B 2 21 1991 18.2 6 22 0.013 9 5 1992 88 A 6 15 0.027 B 2 26 1993 49.4 7 13 0.039 B 2 22 1994 119 7:02 MST 6 7 66.8 6 7 0.067 B 2 28 1995 129 0:00 6 7 104 A 6 7 0.037 B 3 5

(MM) (MM) (MM)

(DD) (DD) (DD)

Annual

Flow

CODE

(m3/s) (m3/s) (m3/s)

Occurrence Occurrence Occurrence

HH:MM

SYMBOL SYMBOL SYMBOL

Occurrence Occurrence Occurrence

Time Zone

Year of Record

Daily Mean Flow Daily Mean Flow

Minimum

B=ice, E=Estimate B=ice, E=Estimate B=ice, E=Estimate

Time of Peak Flow

Maximum

Instantaneous Peak Instantaneous Peak

InstantaneousPeak

Minimum Daily Mean Minimum Daily Mean

Maximum Daily Mean Maximum Daily Mean

Day of Day of Day of

Month of Month of Month of 1996 18.2 A 5 30 1997 43 5 26 0.03 B 3 4 1998 76.5 3:30 MST 7 11 43.6 6 20 1999 22.6 4:15 MST 8 13 15.5 7 5 0.013 B 3 7 2000 4.03 B 3 28 2001 22.8 11:20 MST 6 6 19.1 6 6 2002 75.5 16:00 MST 6 10 64.5 6 10 2003 32.8 21:40 MST 4 25 12.5 4 25 2004 14.5 7 4 2005 389 21:00 MST 6 17 229 6 7 2006 157 18:30 MST 6 15 90.5 6 16 2007 34.1 4:45 MST 6 18 27.1 6 18 2008 220 0:16 MST 5 25 124 5 25 2009 8.53 12:31 MST 5 18 7.85 5 20 2010 39.6 4:16 MST 6 18 33.9 6 18 2011 226 2:03 MST 5 27 186 5 27 2012 148 6:33 MST 6 24 103 6 24 2013 285 15:33 MST 6 20 205 6 21

8.1.2 Recent Direct Discharge Measurements: 05BL013 – Threepoint Creek near Millarville 05BL013 - THREEPOINT CREEK NEAR 05BL013 - THREEPOINT CREEK NEAR 05BL013 - THREEPOINT CREEK NEAR MILLARVILLE MILLARVILLE MILLARVILLE Date Discharge Stage Date Discharge Stage Date Discharge Stage (m^3/s) (m) (m^3/s) (m) (m^3/s) (m) 30/05/1967 283 5.916 22/06/2000 1.378 0.366 18/06/2007 26.759 3.014 31/05/1967 155 4.867 28/07/2000 0.181 0.15 10/07/2007 1.233 2.227 28/02/1994 0.067 0.363 24/08/2000 0.085 0.098 26/07/2007 0.591 2.142 03/03/1994 4.25 0.923 13/09/2000 0.29 0.218 31/08/2007 0.393 2.12 07/03/1994 0.817 0.754 30/10/2000 0.207 0.196 26/10/2007 0.585 2.137 10/03/1994 0.507 0.609 06/03/2001 0.022 0.222 05/03/2008 0.019 1.931 14/03/1994 4.62 0.867 02/04/2001 0.159 0.46 13/03/2008 0.032 1.99 16/03/1994 2.56 0.65 11/04/2001 0.308 0.52 27/03/2008 0.121 2.021 30/03/1994 0.83 0.45 26/04/2001 6.43 0.695 07/05/2008 3.392 2.407 28/04/1994 1.46 0.547 01/06/2001 1.107 0.326 25/05/2008 105.193 3.621 31/05/1994 3.58 0.689 28/06/2001 2.13 0.424 27/05/2008 51.5 2.936 07/06/1994 51.7 1.78 27/07/2001 0.403 0.218 04/06/2008 17.308 2.382 08/06/1994 23.8 1.308 12/09/2001 0.043 0.062 12/06/2008 64.323 3.05 09/06/1994 15.9 1.138 01/11/2001 0.045 0.064 09/07/2008 1.765 1.842 10/06/1994 11.2 1.024 05/03/2002 0.021 0.061 11/08/2008 0.466 1.702 13/06/1994 7.49 0.92 25/03/2002 0.019 0.075 29/09/2008 1.529 1.785 22/06/1994 2.74 0.696 15/04/2002 2.257 0.56 05/11/2008 0.479 1.72 25/07/1994 0.386 0.503 23/04/2002 0.889 0.324 11/03/2009 0.071 1.562 30/08/1994 0.725 0.538 23/05/2002 3.806 0.56 26/03/2009 1.127 1.852 03/10/1994 0.378 0.512 10/06/2002 73.81 1.645 08/04/2009 0.541 1.568 31/10/1994 0.3 0.488 12/06/2002 25.24 1.065 20/04/2009 4.644 1.871 28/02/1995 0.049 03/07/2002 2.007 0.405 26/05/2009 6.519 1.935 08/03/1995 0.037 26/07/2002 0.254 0.169 07/07/2009 3.918 1.822 68

05BL013 - THREEPOINT CREEK NEAR 05BL013 - THREEPOINT CREEK NEAR 05BL013 - THREEPOINT CREEK NEAR MILLARVILLE MILLARVILLE MILLARVILLE Date Discharge Stage Date Discharge Stage Date Discharge Stage (m^3/s) (m) (m^3/s) (m) (m^3/s) (m) 15/03/1995 0.138 0.482 03/09/2002 0.567 0.236 05/08/2009 7.885 1.971 21/03/1995 0.157 0.474 03/10/2002 0.494 0.231 09/09/2009 0.428 1.547 28/03/1995 0.135 0.457 01/11/2002 0.413 0.215 07/10/2009 0.332 1.54 05/04/1995 0.254 0.516 06/03/2003 0.027 0.092 05/11/2009 0.348 1.54 11/04/1995 0.323 0.499 17/03/2003 3.279 0.637 26/02/2010 0.067 1.488 25/04/1995 2.31 0.681 20/03/2003 1.321 0.454 25/03/2010 0.392 1.543 09/05/1995 7.28 0.902 23/04/2003 1.804 0.39 09/04/2010 0.307 1.532 30/05/1995 13.6 1.076 30/05/2003 2.885 0.449 07/05/2010 1.477 1.664 08/06/1995 30.5 1.329 09/07/2003 1.786 0.386 20/05/2010 4.926 1.885 12/06/1995 10 0.88 24/07/2003 0.317 0.184 08/06/2010 6.223 1.924 26/06/1995 6.89 0.798 07/08/2003 0.488 0.225 08/07/2010 1.647 1.713 02/08/1995 1.89 0.511 17/09/2003 0.39 0.208 04/08/2010 1.905 1.716 29/08/1995 0.448 0.344 28/10/2003 0.145 0.138 10/09/2010 2.504 1.774 28/02/1996 0.082 24/02/2004 0.032 0.091 07/10/2010 1.513 1.688 12/03/1996 3.83 1.012 09/03/2004 0.039 0.08 28/10/2010 0.761 1.621 13/03/1996 1.67 0.816 10/03/2004 0.039 0.08 04/03/2011 0.084 1.552 19/03/1996 1.09 0.688 22/03/2004 0.655 0.32 25/03/2011 0.095 1.539 11/04/1996 3.26 0.624 19/04/2004 1.046 0.304 08/04/2011 0.673 1.619 24/04/1996 3.1 0.568 04/05/2004 1.222 0.326 27/04/2011 10.237 2.108 27/05/1996 6.61 0.762 20/05/2004 3.982 0.522 27/05/2011 170.893 3.66 24/06/1996 5.62 0.692 28/06/2004 1.853 0.396 28/05/2011 76.657 2.851 30/07/1996 0.585 0.29 30/07/2004 0.841 0.29 31/05/2011 25.476 2.262 03/09/1996 0.048 0.084 30/08/2004 7.79 0.668 22/06/2011 14.74 2.159 08/10/1996 0.306 0.238 27/09/2004 1.243 0.324 04/08/2011 0.852 1.665 69

05BL013 - THREEPOINT CREEK NEAR 05BL013 - THREEPOINT CREEK NEAR 05BL013 - THREEPOINT CREEK NEAR MILLARVILLE MILLARVILLE MILLARVILLE Date Discharge Stage Date Discharge Stage Date Discharge Stage (m^3/s) (m) (m^3/s) (m) (m^3/s) (m) 28/02/1997 0.048 0.1 25/10/2004 0.52 0.263 24/08/2011 0.357 1.601 19/03/1997 0.082 0.178 07/03/2005 1.19 0.572 27/10/2011 0.253 1.587 24/03/1997 2.92 0.6 23/03/2005 0.533 0.255 09/03/2012 0.0428 1.637 29/04/1997 1.77 0.47 14/04/2005 1.151 0.357 28/03/2012 0.4078 1.652 28/05/1997 24.9 1.107 12/05/2005 5.082 0.582 12/04/2012 0.8519 1.659 03/07/1997 2.04 0.46 08/06/2005 163.766 4.252 08/05/2012 6.1918 1.903 20/08/1997 1.9 0.47 10/06/2005 48.316 3.073 06/06/2012 42.157 2.582 26/09/1997 0.247 0.166 14/06/2005 28.132 2.771 27/06/2012 50.2196 2.557 30/10/1997 0.217 0.16 18/06/2005 154.39 3.858 31/07/2012 1.494 1.621 26/02/1998 0.05 0.07 28/06/2005 201.15 4.421 29/08/2012 0.4997 1.538 23/03/1998 0.017 0.04 29/06/2005 85.956 3.23 02/10/2012 0.3176 1.519 26/03/1998 0.015 0.03 21/07/2005 2.95 1.866 30/10/2012 0.3184 1.516 06/04/1998 3.184 0.656 09/08/2005 0.811 1.709 26/02/2013 0.0148 1.461 04/05/1998 2.627 0.51 11/08/2005 1.401 1.767 22/03/2013 0.3604 1.75 28/05/1998 32.5 1.285 01/09/2005 1.702 1.785 25/04/2013 1.0584 1.617 02/07/1998 16.707 0.96 12/09/2005 15.5 2.266 31/05/2013 14.3936 2.052 27/07/1998 1.961 0.41 28/09/2005 3.58 1.878 23/06/2013 49.7403 2.54 11/08/1998 0.697 0.259 25/10/2005 1.868 1.764 26/06/2013 18.3716 2.074 17/09/1998 0.161 0.12 21/02/2006 0.039 1.573 22/08/2013 2.0002 1.637 02/11/1998 0.479 0.204 29/03/2006 0.711 1.754 03/10/2013 1.1304 1.588 26/02/1999 0.029 0.064 13/04/2006 2.819 1.858 25/10/2013 1.1101 1.583 11/03/1999 0.028 0.062 08/05/2006 1.742 1.75 24/02/2014 0.1424 1.538 01/04/1999 0.142 0.13 08/06/2006 1.436 1.738 17/03/2014 4.1737 2.073 07/05/1999 1.094 0.34 16/06/2006 80.8 3.078 10/04/2014 7.1528 1.861 70

8.1.3 Station Visit Frequency: 05BL013 – Threepoint Creek near Millarville

8.1.4 Ratings Curves No.9 and no. 11 Showing Recent Measurements: 05BL013 – Threepoint Creek near Millarville

8.1.5 Measurement Departure from Rating Curve by Stage: 05BL013 – Threepoint Creek near Millarville

8.1.6 Measurement Departure from Rating Curve by Discharge: 05BL013 – Threepoint Creek near Millarville

8.1.7 Duration of Annual Floods from Peak Hydrographs: 05BL013 – Threepoint Creek near Millarville

8.1.8 Annual Flood Volume VS Annual Max. Inst. Flow: 05BL013 – Threepoint Creek near Millarville

8.1.9 Annual Flood Volume VS Annual Max. Daily Flow: 05BL013 – Threepoint Creek near Millarville

8.1.10 Rank of Annual Extremes by Peak and by Volume: 05BL013 – Threepoint Creek near Millarville

8.1.11 Compare Annual Maximum Instantaneous Peak to Maximum Daily: 05BL013 – Threepoint Creek near Millarville

8.1.12 Combined Annual Peak Hydrographs: 05BL013 – Threepoint Creek near Millarville

8.1.13 Threepoint Millarville - 1909

8.1.14 Threepoint Millarville - 1912

8.1.15 Threepoint Millarville - 1913

8.1.16 Threepoint Millarville - 1914

8.1.17 Threepoint Millarville - 1915

8.1.18 Threepoint Millarville - 1916

8.1.19 Threepoint Millarville - 1966

8.1.20 Threepoint Millarville – 1967

8.1.21 Threepoint Millarville - 1968

8.1.22 Threepoint Millarville – 1969

8.1.23 Threepoint Millarville - 1970

8.1.24 Threepoint Millarville - 1971

8.1.25 Threepoint Millarville - 1972

8.1.26 Threepoint Millarville - 1973

8.1.27 Threepoint Millarville - 1974

8.1.28 Threepoint Millarville - 1975

8.1.29 Threepoint Millarville - 1976

8.1.30 Threepoint Millarville - 1977

8.1.31 Threepoint Millarville - 1978

100

8.1.32 Threepoint Millarville - 1979

101

8.1.33 Threepoint Millarville - 1980

102

8.1.34 Threepoint Millarville - 1981

103

8.1.35 Threepoint Millarville - 1982

104

8.1.36 Threepoint Millarville - 1983

105

8.1.37 Threepoint Millarville - 1984

106

8.1.38 Threepoint Millarville - 1985

107

8.1.39 Threepoint Millarville - 1986

108

8.1.40 Threepoint Millarville - 1987

109

8.1.41 Threepoint Millarville - 1988

110

8.1.42 Threepoint Millarville - 1989

111

8.1.43 Threepoint Millarville - 1990

112

8.1.44 Threepoint Millarville - 1991

113

8.1.45 Threepoint Millarville - 1992

114

8.1.46 Threepoint Millarville - 1993

115

8.1.47 Threepoint Millarville - 1994

116

8.1.48 Threepoint Millarville - 1995

117

8.1.49 Threepoint Millarville - 1996

118

8.1.50 Threepoint Millarville - 1997

119

8.1.51 Threepoint Millarville - 1998

120

8.1.52 Threepoint Millarville - 1999

121

8.1.53 Threepoint Millarville - 2000

122

8.1.54 Threepoint Millarville - 2001

123

8.1.55 Threepoint Millarville - 2002

124

8.1.56 Threepoint Millarville - 2003

125

8.1.57 Threepoint Millarville - 2004

126

8.1.58 Threepoint Millarville - 2005

127

8.1.59 Threepoint Millarville - 2006

128

8.1.60 Threepoint Millarville - 2007

129

8.1.61 Threepoint Millarville - 2008

130

8.1.62 Threepoint Millarville - 2009

131

8.1.63 Threepoint Millarville - 2010

132

8.1.64 hreepoint Millarville - 2011

133

8.1.65 Threepoint Millarville - 2012

134

8.1.66 Threepoint Millarville - 2013

135

9 05BL014 – Sheep River at Black Diamond

136

9.1.1 Summary of Peak Flow Data for 05BL014 – Sheep River at Black Diamond

Annual

Flow

CODE

(m3/s) (m3/s) (m3/s)

HH:MM

SYMBOL SYMBOL SYMBOL

Time Zone

Year of Record

of Occurrence (DD)

Daily Mean Flow Daily Mean Flow

B=ice, E=Estimate Maximum B=ice, E=Estimate B=ice, E=Estimate

Minimum

Time of Peak Flow

Instantaneous Peak Instantaneous Peak

InstantaneousPeak

Minimum Daily Mean Minimum Daily Mean

Maximum Daily Mean Maximum Daily Mean

Day of Occurrence (DD) Day Day of Occurrence (DD)

Month of Occurrence (MM) Month of Occurrence (MM) Month of Occurrence (MM) 1911 66.8 8 7 1912 51.8 7 8 1913 29.4 6 28 1914 19.3 6 4 1915 133 6 26 1916 200 6 28 1969 96.3 E 6 29 0.348 12 8 1970 195 4:59 MST 6 14 122 6 14 0.626 3 1 1971 92 7:00 MST 6 6 71.9 6 6 0.646 B 12 28 1972 45.9 2:00 MST 6 1 41.1 6 1 0.547 1 11 1973 39.4 2:00 MST 6 7 34 6 7 0.677 11 8 1974 55.8 23:59 MST 6 15 50.7 6 16 0.731 3 23 1975 104 2:30 MST 6 20 83.8 6 20 0.841 1 17 1976 45 3:00 MST 8 6 32.3 8 6 0.606 11 22 1977 20.9 9:30 MST 8 13 15.2 8 14 0.668 11 18 1978 53.2 23:59 MST 6 4 43.3 6 6 0.614 2 26 1979 39.6 2:00 MST 5 27 29.6 5 27 0.498 11 20 1980 69.1 22:30 MST 6 3 59.2 6 3 0.69 4 1 1981 122 2:00 MST 5 26 87 5 26 0.768 B 12 31 137

Annual

Flow

CODE

(m3/s) (m3/s) (m3/s)

HH:MM

SYMBOL SYMBOL SYMBOL

Time Zone

Year of Record

of Occurrence (DD)

Daily Mean Flow Daily Mean Flow

B=ice, E=Estimate Maximum B=ice, E=Estimate B=ice, E=Estimate

Minimum

Time of Peak Flow

Instantaneous Peak Instantaneous Peak

InstantaneousPeak

Minimum Daily Mean Minimum Daily Mean

Maximum Daily Mean Maximum Daily Mean

Day of Occurrence (DD) Day Day of Occurrence (DD)

Month of Occurrence (MM) Month of Occurrence (MM) Month of Occurrence (MM) 1982 26.3 23:51 MST 6 14 21.8 6 15 0.53 B 1 7 1983 47 1:26 MST 4 25 24.7 4 25 0.333 11 23 1984 24.8 0:19 MST 5 31 15.1 5 31 0.56 B 12 27 1985 82.2 19:09 MST 9 12 50 9 13 0.517 B 2 13 1986 39.6 1:29 MST 5 29 33.3 5 28 0.748 B 2 18 1987 24.2 10:37 MST 7 19 22.7 7 19 0.564 B 2 26 1988 29.4 6:02 MST 6 8 24.9 6 8 0.47 B 2 4 1989 19.4 2:58 MST 5 11 17.3 5 11 0.6 B 3 1 1990 207 1:00 MST 5 26 128 5 26 0.54 B 2 17 1991 60.7 12:50 MST 6 21 48.2 5 20 0.717 B 3 1 1992 150 2:12 MST 6 15 98.2 6 14 0.7 B 2 20 1993 102 6 16 0.6 B 11 24 1994 81.6 2:49 MST 6 7 50.7 6 7 0.78 B 1 16 1995 366 21:54 MST 6 6 161 6 6 0.443 B 3 2 1996 40 2:00 MST 6 8 36.1 6 8 0.6 B 12 30 1997 63.9 1:50 MST 6 1 49.1 5 31 0.56 B 1 25 1998 121 4:50 MST 5 23 88.1 6 19 0.442 B 12 21 1999 25.3 21:00 MST 7 4 22.1 7 7 0.76 B 1 23 2000 18.5 17:00 MST 6 9 17.2 6 9

138

Annual

Flow

CODE

(m3/s) (m3/s) (m3/s)

HH:MM

SYMBOL SYMBOL SYMBOL

Time Zone

Year of Record

of Occurrence (DD)

Daily Mean Flow Daily Mean Flow

B=ice, E=Estimate Maximum B=ice, E=Estimate B=ice, E=Estimate

Minimum

Time of Peak Flow

Instantaneous Peak Instantaneous Peak

InstantaneousPeak

Minimum Daily Mean Minimum Daily Mean

Maximum Daily Mean Maximum Daily Mean

Day of Occurrence (DD) Day Day of Occurrence (DD)

Month of Occurrence (MM) Month of Occurrence (MM) Month of Occurrence (MM) 2001 35.8 20:50 MST 6 5 33.1 6 5 0.244 B 11 28 2002 67.8 23:55 MST 6 16 55 6 16 0.451 B 1 29 2003 89.2 15:25 MST 4 25 34.2 4 25 0.55 B 1 23 2004 31.8 16:00 MST 8 26 30.5 8 26 0.4 B 1 27 2005 380 22:05 MST 6 17 245 6 7 0.519 B 2 21 2006 126 20:35 MST 6 15 72.5 6 16 0.733 B 2 18 2007 35.5 19:50 MST 6 6 30.3 6 6 0.624 B 3 3 2008 259 20:15 MST 5 24 146 5 24 0.583 B 1 20 2009 30.8 0:55 MST 5 31 23.3 5 30 0.75 B 2 15 2010 47.7 23:45 MST 6 17 39 6 18 0.57 B 2 23 2011 185 23:15 MST 5 26 146 5 27 0.581 B 12 31 2012 185 4:15 MST 6 24 131 6 24 0.692 B 1 1

139

9.1.2 Recent Direct Discharge Measurements: 05BL014 – Sheep River at Black Diamond 05Bl014 - Sheep River at Black 05Bl014 - Sheep River at Black 05Bl014 - Sheep River at Black Diamond Diamond Diamond Date/Time Discharge Stage Date/Time Discharge Stage Date/Time Discharge Stage (m^3/s) (m) (m^3/s) (m) (m^3/s) (m) 04/01/1994 1.46 0.67 28/07/2000 3.09 1.324 04/02/2008 0.794 1.277 26/01/1994 0.919 0.746 07/09/2000 3.143 1.334 05/03/2008 0.854 1.196 16/02/1994 0.94 0.643 30/10/2000 1.578 1.176 27/03/2008 1.03 1.136 03/03/1994 2.87 1.386 06/12/2000 0.871 1.157 07/05/2008 4.299 1.31 14/03/1994 2.13 1.089 05/01/2001 0.784 1.138 25/05/2008 96.409 2.228 30/03/1994 2.08 0.556 29/01/2001 0.492 1.272 27/05/2008 51.912 2.027 26/04/1994 2.1 0.511 06/03/2001 0.547 1.115 04/06/2008 59.025 1.922 31/05/1994 7.61 0.707 02/04/2001 0.719 1.118 09/07/2008 9.685 1.604 08/06/1994 27.2 1.013 26/04/2001 6.01 1.587 11/08/2008 3.757 1.437 09/06/1994 19.5 0.918 01/06/2001 6.567 1.526 29/09/2008 3.601 1.417 10/06/1994 15.6 0.862 28/06/2001 8.234 1.55 05/11/2008 1.962 1.326 13/06/1994 11.7 0.798 27/07/2001 3.232 1.302 09/12/2008 1.118 1.333 22/06/1994 6.58 0.696 12/09/2001 1.561 1.164 06/01/2009 0.892 1.461 25/07/1994 3.16 0.595 01/11/2001 0.875 1.112 03/02/2009 0.907 1.502 30/08/1994 5.96 0.676 26/11/2001 0.336 1.126 11/03/2009 0.788 1.574 03/10/1994 1.97 0.541 19/12/2001 0.795 1.112 26/03/2009 1.467 1.506 25/10/1994 2.22 0.545 07/01/2002 0.503 1.078 08/04/2009 1.6 1.31 23/11/1994 1.2 0.61 31/01/2002 0.574 1.156 20/04/2009 3.63 1.444 14/12/1994 1.11 0.797 05/03/2002 0.617 1.084 26/05/2009 17.326 1.761 05/01/1995 0.853 0.925 25/03/2002 0.792 1.155 07/07/2009 11.224 1.649 23/01/1995 0.8 0.941 22/04/2002 2.351 1.249 05/08/2009 22.38 1.817 16/02/1995 0.86 0.69 23/05/2002 11.462 1.672 09/09/2009 2.952 1.383 08/03/1995 0.655 0.59 10/06/2002 52.638 2.264 07/10/2009 2.707 1.362

140

05Bl014 - Sheep River at Black 05Bl014 - Sheep River at Black 05Bl014 - Sheep River at Black Diamond Diamond Diamond Date/Time Discharge Stage Date/Time Discharge Stage Date/Time Discharge Stage (m^3/s) (m) (m^3/s) (m) (m^3/s) (m) 21/03/1995 1.16 0.575 12/06/2002 32.427 2.079 05/11/2009 2.289 1.332 28/03/1995 1.05 0.503 03/07/2002 13.844 1.866 09/12/2009 0.833 1.421 05/04/1995 1.43 0.505 26/07/2002 5.052 1.763 06/01/2010 0.908 1.516 11/04/1995 1.21 0.478 03/09/2002 3.51 1.728 03/02/2010 0.632 1.48 25/04/1995 2.37 0.557 03/10/2002 3.555 1.724 26/02/2010 0.6 1.348 30/05/1995 38 1.075 24/10/2002 2.48 1.73 25/03/2010 1.351 1.268 07/06/1995 173 2.777 29/11/2002 1.219 1.563 09/04/2010 1.58 1.289 08/06/1995 63 1.006 10/01/2003 0.949 1.854 07/05/2010 2.01 1.335 09/06/1995 42.9 0.767 03/02/2003 0.794 1.922 08/06/2010 17.741 1.763 14/06/1995 25.1 0.492 06/03/2003 0.785 1.853 08/07/2010 8.08 1.589 26/06/1995 24.3 0.524 17/03/2003 1.593 2.155 04/08/2010 6.234 1.512 01/08/1995 6.04 0.27 23/04/2003 3.372 1.724 07/10/2010 5.273 1.483 28/08/1995 3.03 0.101 30/05/2003 16.58 1.893 28/10/2010 3.02 1.36 29/09/1995 3.59 0.084 09/07/2003 5.664 1.703 30/11/2010 1.993 1.503 08/01/1996 1.19 0.446 07/08/2003 2.303 1.601 05/01/2011 1.254 1.491 29/01/1996 0.882 0.461 17/09/2003 2.273 1.605 01/02/2011 1.167 1.331 21/02/1996 1.43 0.782 28/10/2003 2.7 1.616 03/03/2011 0.862 1.36 13/03/1996 2.71 0.764 09/12/2003 0.876 1.68 25/03/2011 0.996 1.237 19/03/1996 1.88 0.391 05/01/2004 0.681 1.769 08/04/2011 1.22 1.309 11/04/1996 4.23 0.104 02/02/2004 0.831 1.671 27/04/2011 6.085 1.514 24/04/1996 3.5 0.076 24/02/2004 1.027 1.617 27/05/2011 145.583 2.605 27/05/1996 19.1 0.467 22/03/2004 1.093 1.634 28/05/2011 72.195 2.195 24/06/1996 25.2 0.573 19/04/2004 1.936 1.586 31/05/2011 29.513 1.82 30/07/1996 5.29 0.135 20/05/2004 10.694 1.814 22/06/2011 33.209 1.88

141

05Bl014 - Sheep River at Black 05Bl014 - Sheep River at Black 05Bl014 - Sheep River at Black Diamond Diamond Diamond Date/Time Discharge Stage Date/Time Discharge Stage Date/Time Discharge Stage (m^3/s) (m) (m^3/s) (m) (m^3/s) (m) 03/09/1996 2.22 -0.002 28/06/2004 11.332 1.812 04/08/2011 4.132 1.438 08/10/1996 3.05 0.068 30/07/2004 4.089 1.646 24/08/2011 2.771 1.387 31/10/1996 1.93 -0.014 30/08/2004 17.548 1.935 27/10/2011 2.071 1.329 25/11/1996 1.45 0.194 27/09/2004 4.151 1.717 28/11/2011 1.686 1.358 16/12/1996 1.01 1.158 25/10/2004 2.764 1.717 03/01/2012 1.0177 1.289 09/01/1997 0.855 1.226 06/12/2004 1.064 1.704 30/01/2012 0.8808 1.451 30/01/1997 0.76 1.282 04/01/2005 0.875 2.1 09/03/2012 1.1971 1.402 20/02/1997 1.29 1.252 01/02/2005 1.389 1.764 28/03/2012 1.1881 1.296 19/03/1997 0.993 1.236 07/03/2005 1.415 1.789 12/04/2012 1.8833 1.335 22/03/1997 5.15 1.383 23/03/2005 1.265 1.781 08/05/2012 8.3568 1.55 26/03/1997 3.43 1.086 14/04/2005 2.057 1.656 06/06/2012 95.5201 2.375 29/04/1997 3.13 1.05 12/05/2005 7.74 1.797 28/06/2012 46.0436 2.016 28/05/1997 26.7 1.623 07/06/2005 277.377 3.322 31/07/2012 6.2556 1.53 03/07/1997 9.42 1.361 10/06/2005 63.179 2.385 29/08/2012 3.2193 1.432 20/08/1997 7.01 1.282 19/06/2005 84.277 2.212 02/10/2012 2.1557 1.369 26/09/1997 2.62 1.066 28/06/2005 153.909 2.726 30/10/2012 2.4025 1.375 30/10/1997 1.98 1.014 29/06/2005 78.34 2.182 26/11/2012 1.0772 1.349 02/12/1997 1.11 1.125 22/07/2005 8.28 1.36 07/01/2013 1.0017 1.405 06/01/1998 0.815 1.299 09/08/2005 4.376 1.246 05/02/2013 1.3788 1.424 03/02/1998 0.841 1.354 11/08/2005 6.015 1.297 25/02/2013 0.7608 1.436 26/02/1998 0.789 1.25 31/08/2005 6.346 1.324 22/03/2013 1.1886 0 26/03/1998 0.956 1.16 28/09/2005 8.265 1.344 25/04/2013 1.5799 1.333 07/04/1998 3.313 1.376 25/10/2005 5.513 1.265 31/05/2013 33.1466 1.95 04/05/1998 8.711 1.326 06/12/2005 1.309 1.4 01/08/2013 6.5613 1.042

142

05Bl014 - Sheep River at Black 05Bl014 - Sheep River at Black 05Bl014 - Sheep River at Black Diamond Diamond Diamond Date/Time Discharge Stage Date/Time Discharge Stage Date/Time Discharge Stage (m^3/s) (m) (m^3/s) (m) (m^3/s) (m) 28/05/1998 50.155 1.964 03/01/2006 1.755 1.291 22/08/2013 5.6294 1.222 22/06/1998 37.2 2.15 27/01/2006 1.467 1.264 03/10/2013 5.3186 1.19 23/06/1998 32.7 2.094 21/02/2006 1.273 1.241 25/10/2013 3.6467 1.129 02/07/1998 27.537 2.007 23/03/2006 1.063 1.131 31/10/2013 4.08 1.137 20/07/1998 8.227 1.632 19/04/2006 1.473 1.129 11/12/2013 1.6016 1.313 17/09/1998 2.111 1.298 30/05/2006 8.193 1.362 06/01/2014 1.4141 1.001 02/11/1998 1.888 1.285 16/06/2006 66.848 2.056 03/02/2014 1.1719 1.122 30/11/1998 0.597 1.261 17/06/2006 47.665 1.877 24/02/2014 1.1283 1.078 04/01/1999 1.044 1.298 12/07/2006 5.891 1.374 17/03/2014 4.2532 1.08 01/02/1999 0.895 1.368 17/08/2006 4.005 1.314 24/04/2014 5.0262 1.033 11/03/1999 0.877 1.271 06/09/2006 2.245 1.231 05/06/2014 18.9901 1.394 01/04/1999 1.221 1.355 26/10/2006 2.382 1.235 20/06/2014 64.9316 1.858 07/05/1999 2.539 1.337 04/12/2006 1.956 1.585 21/06/2014 47.0105 1.656 04/06/1999 20.209 1.838 08/01/2007 1.3 1.49 02/07/2014 17.3076 1.126 28/06/1999 14.3 1.724 05/02/2007 1.077 1.394 17/07/2014 7.0406 0.876 04/08/1999 6.565 1.509 26/02/2007 0.907 1.321 07/08/2014 3.7491 0.749 14/09/1999 2.893 1.36 08/03/2007 2.237 1.535 02/09/2014 3.956 0.752 01/11/1999 1.475 1.194 30/03/2007 1.579 1.242 06/10/2014 4.68 0.788 29/11/1999 1.762 1.266 26/04/2007 4.136 1.322 03/11/2014 2.8246 0.686 04/01/2000 0.829 1.241 31/05/2007 15.76 1.575 08/12/2014 2.1616 0.778 01/02/2000 0.704 1.194 21/06/2007 19.052 1.609 05/01/2015 1.4131 0.87 25/02/2000 0.912 1.178 20/07/2007 6.165 1.364 02/02/2015 1.3885 0.82 21/03/2000 0.945 1.152 23/08/2007 2.545 1.216 23/02/2015 1.2584 0.603 28/03/2000 2.351 1.345 13/09/2007 4.522 1.311 16/03/2015 2.4763 0.655

143

144

9.1.3 Station Visit Frequency: 05BL014 – Sheep River at Black Diamond

145

9.1.4 Rating Curve No. 16 Showing Recent Measurements: 05BL014 – Sheep River at Black Diamond

146

9.1.5 Measure Departure from Discharge by Stage: 05BL014 – Sheep River at Black Diamond

147

9.1.6 Measurement Departure from Rating by Discharge: 05BL014 – Sheep River at Black Diamond

148

9.1.7 Duration of Annual Flood from Peak Hydrographs: 05BL014 – Sheep River at Black Diamond

149

9.1.8 Annual Flood Volume Vs. Annual Max. Inst. Flow: 05BL014 – Sheep River at Black Diamond

150

9.1.9 Annual Flood Volume Vs. Annual Max. Daily Flow: 05BL014 – Sheep River at Black Diamond

151

9.1.10 Rank of Annual Extremes by Peak and Volume: 05BL014 – Sheep River at Black Diamond

152

9.1.11 Compare Annual Maximum Instantaneous Peak to Maximum Daily: 05BL014 – Sheep River at Black Diamond

153

9.1.12 Combined Annual Peak Hydrographs: 05BL014 – Sheep River at Black Diamond

154

9.1.13 Sheep River Black Diamond - 1911

155

9.1.14 Sheep River Black Diamond - 1912

156

9.1.15 Sheep River Black Diamond - 1913

157

9.1.16 Sheep River Black Diamond - 1914

158

9.1.17 Sheep River Black Diamond - 1915

159

9.1.18 Sheep River Black Diamond - 1916

160

9.1.19 Sheep River Black Diamond - 1969

161 The Symbol “A” indicates Partial Day Record. The Symbol “E” indicates an estimated value.

9.1.20 Sheep River Black Diamond - 1970

162

9.1.21 Sheep River Black Diamond - 1971

163

9.1.22 Sheep River Black Diamond - 1972

164

9.1.23 Sheep River Black Diamond - 1973

165

9.1.24 Sheep River Black Diamond - 1974

166

9.1.25 Sheep River Black Diamond - 1975

167

9.1.26 Sheep River Black Diamond - 1976

168

9.1.27 Sheep River Black Diamond - 1977

169

9.1.28 Sheep River Black Diamond - 1978

170

9.1.29 Sheep River Black Diamond - 1979

171

9.1.30 Sheep River Black Diamond - 1980

172

9.1.31 Sheep River Black Diamond - 1981

173

9.1.32 Sheep River Black Diamond - 1982

174

9.1.33 Sheep River Black Diamond - 1983

175

9.1.34 Sheep River Black Diamond - 1984

176

9.1.35 Sheep River Black Diamond - 1985

177

9.1.36 Sheep River Black Diamond - 1986

178

9.1.37 Sheep River Black Diamond - 1987

179

9.1.38 Sheep River Black Diamond - 1988

180

9.1.39 Sheep River Black Diamond - 1989

181

9.1.40 Sheep River Black Diamond - 1990

182 The Symbol “A” indicates Partial Day Record. The Symbol “E” indicates an estimated value.

9.1.41 Sheep River Black Diamond - 1991

183

9.1.42 Sheep River Black Diamond - 1992

184

9.1.43 Sheep River Black Diamond - 1993

185

9.1.44 Sheep River Black Diamond - 1994

186

9.1.45 Sheep River Black Diamond - 1995

187

9.1.46 Sheep River Black Diamond - 1996

188

9.1.47 Sheep River Black Diamond - 1997

189

9.1.48 Sheep River Black Diamond - 1998

190

9.1.49 Sheep River Black Diamond - 1999

191

9.1.50 Sheep River Black Diamond - 2000

192 The Symbol “A” indicates partial day record.

9.1.51 Sheep River Black Diamond - 2001

193

9.1.52 Sheep River Black Diamond - 2002

194

9.1.53 Sheep River Black Diamond - 2003

195

9.1.54 Sheep River Black Diamond - 2004

196

9.1.55 Sheep River Black Diamond - 2005

197

9.1.56 Sheep River Black Diamond - 2006

198

9.1.57 Sheep River Black Diamond - 2007

199

9.1.58 Sheep River Black Diamond - 2008

200

9.1.59 Sheep River Black Diamond - 2009

201

9.1.60 Sheep River Black Diamond - 2010

202

9.1.61 Sheep River Black Diamond - 2011

203

9.1.62 Sheep River Black Diamond – 2012

204

10 Water Survey of Canada Station Descriptions

205

10.1.1 Station Description for 05BL012 – Sheep River at Okotoks

206

207

10.1.2 Station Description for 05BL013 – Threepoint Creek near Millarville

208

209

10.1.3 Station Description for 05BL014 – Sheep River at Black Diamond

210

211

212