Report No. 9073-1

Quamichan Lake Outlet Control

Prepared for:

Friends of Quamichan Lake Stewardship Committee

Prepared by: D.G.V. Engineering Services Ltd. February 1, 2008

TABLE OF CONTENTS Page 1. OVERVIEW ...... 1

2. INTRODUCTION ...... 3 2.1.1 Hydrology: ...... 4 2.1.2 Survey of the Lake Outlet Channel...... 5 2.1.3 Control Structure Concept: ...... 5 2.1.4 Management of Beaver Activity: ...... 7 2.1.5 Management Regime of Lake Level and Creek Discharge...... 9 2.1.6 Habitat Loss Footprint...... 10 2.1.7 Channel Maintenance...... 10 2.1.8 Monitoring...... 10

3. DISCUSSION ...... 10 3.1 Lake Level Data ...... 10 3.1.1 New Reference Mark ...... 11 3.1.2 Water Survey of Canada (WSC) station 08HA020 ...... 11 3.1.3 Stewart Data (6387 Lakes Road):...... 11 3.1.4 Dr. David Groves ...... 12 3.2 Quamichan Creek Flow...... 12 3.2.1 Water Survey of Canada (WSC) station 08HA021 ...... 12 3.3 Channel Capacity ...... 12

4. DEVELOPING STORAGE FOR FISH ENHANCEMENT...... 13

5. CONCLUSION AND RECOMMENDATIONS ...... 14

6. DISCLAIMER...... 15

7. CERTIFICATION ...... 16

8. ATTACHMENTS...... 17

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1. OVERVIEW

DGV Engineering Services Ltd. was retained to review the conditions that impact the water level and outflow of Quamichan Lake, near Duncan BC. The terms of reference included the following items: • Limited hydrological assessment • Site survey using land survey techniques • Site materials evaluation and mapping • Fisheries compensation area evaluation • Conceptual weir design(s) and location(s) • Recommendation for a management regime

The terms of reference did not include: • Assessment of Fish Habitat • Assessment of factors related to fisheries productivity • Assessment factors around water flow that related to fish migration, spawning or rearing • Assessment of Water Quality • Public education issues related to beaver activity or beaver management

This report addresses each of these items in terms of providing some basis for attempting to address the lake management conflicts that exist. The community issue that needs to be addressed is the need for, and nature of, the management of the lake water level.

Agricultural interests around the lake are best served by a lower lake level in the spring and early summer, thus allowing access to low lying productive land areas. Generally, higher lake levels best serve fisheries and wildlife habitats by providing some storage that could be used to improve summer stream flows. Under current conditions, an active beaver dam in the outlet stream has eliminated effective creek flows thus defeating both the access to low lying lands by the farms and fish passage.

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The Friends of Quamichan Lake Stewardship Committee has questioned whether a control structure could be installed to operate such that:

¾ Early spring lake levels would be dropped to facilitate farm land access. The current channel, if clear, has provided adequate access to farm lands. However if free drainage is allowed to continue throughout the spring Quamichan Creek will be dried in the summer. ¾ When the lake level is low enough to allow drainage and access to the farm land, the flow from the lake would be reduced and controlled so that the lake level would achieve limited recovery by holding water from late spring rains. The lake level would thus be controlled to promote the aquatic environment, but still low enough to aid the farmers throughout the summer period. ¾ Some of the retained storage would be available in the late summer to assist in fish migration. ¾ Fish passage would be maintained past the structure for a larger portion of the year.

The existing creek channel is an excavated channel that is founded on bedrock. The channel has essentially no slope from the lake outlet near the existing footbridge at Art Mann Park for at least 160 m to the old stream flow station on private property. This excavated flat channel in rock extends an estimated 150 m further downstream before a clearly defined break in slope where the stream begins to lose elevation.

The main impediment to lowering of the lake level to recent "normal" water levels is the existing beaver dam and its associated mound of debris and sediment. Removal of this obstruction will immediately lead to lowering of the lake water level and may expose other important flow obstructions upstream. In general, the channel has a considerable amount of woody debris and overhanging material, but despite this the channel has reasonable hydraulic capacity. The channel capacity is primarily limited by the lack of slope. Inspection and hand clearing of specific flow impediments on a regular basis are preferred over the wholesale machine clearing of the creek bed if aesthetic and environmental impacts are to be minimized.

There is no easy means by which a significant lowering of the summer lake levels can be achieved. Lowering summer lake levels more than could be achieved through simple clearing of the creek bed would involve deepening the channel in bedrock over approximately 310 m of length since the creek is typically essentially dry in the summer.

A simple control structure is suggested that could provide some active manipulation of the lake water level in the summer, presumably with the intent of early lowering of the lake level by unrestricted drainage followed by attempting to restrict discharge in May and June to hold water in the lake to maintain and possibly raise lake levels.

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Any proposed lake management strategy must consider the compromise between agricultural land access and residential and recreational uses of the lake, water supply for the water license holders and environmental concerns. The operational rules would result from input from these interests and are therefore beyond the scope of this study.

2. INTRODUCTION

Quamichan Lake is a relatively large shallow lake located approximately 2 km north east of Duncan. The lake has an area of 288 hectares, a mean depth of approximately 4 m, and a watershed catchment area of about 18.8 km2. The general topography is shown in Figure 21 and the lake bathymetry is illustrated as Figure 32. The lake occupies part of the relatively flat lowland area formed by glacial infilling and surrounded by relatively steep bedrock structures including Mount Tzouhalem to the east, Maple Mountain and Mount Richards to the north and Mount Prevost to the west beyond Somenos Lake and wetlands and the northern portion of Duncan.

The area immediately around the lake is fully developed primarily for agricultural and rural residential uses. The watershed boundaries are somewhat indistinct to the west due to imposed road and agricultural drainage structures that likely modify the natural drainage structure as well as possible sub-surface connections with the Somenos Lake and wetlands.

The lake appears to be defined by shallow bedrock at the margins, particularly at the outlet where Quamichan Creek drains the lake 1.25 km to the south where it joins the Cowichan River.

The lake provides habitat for Brown Catfish, Rainbow and Cutthroat Trout. Quamichan Creek is a migration route for fish between the lake and the Cowichan River, and likely provides rearing habitat. The creek and associated riparian area is habitat for a variety of wildlife.

The intent of the study is to correlate the various lake level datasets, define the discharge character of Quamichan Lake and develop a structure concept that may provide some control of the lake levels. High spring lake levels adversely impact agricultural activities, while low to zero flows in the summer are detrimental to fish values.

1 From NTS 1:50 000 map, 92 B/13, Published by Energy Mines and Natural Resources, Canada 2 From Ministry of Environment, BC

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The study involved land survey of the key reach of Quamichan Creek from the lake outlet sufficiently downstream to establish a location for a control structure. In addition, it identifies and correlates several sources of lake level data that exist. A land survey of the lake outlet was done and a suggestion for a control structure is provided.

2.1.1 Hydrology: The watershed that serves the lake is outlined in Appendix A, Figure 2 and clearly shows that the inputs to the lake are local. The watershed is relatively small and there are no other significant storage elements such as other lakes, groundwater or high elevation snow pack typical of many Vancouver Island watersheds.

The review of the lake level data and the available stream flow data suggest that the lake responds exclusively to local precipitation. The nearest long term climate station is the Duncan Forestry site, which was located approximately 5 km due south of the lake outlet. Appendix B, Table 2 provides the 30-year Climate Normal summary. This site records average annual precipitation of 1039 mm, of which about 20% falls in the April through August period corresponding to the management period of interest. This station is representative of the site.

The graph of lake level data (Appendix B, Figure 9) clearly shows that the opportunity for capturing significant water for storage after early April is limited but could be exploited. The lake responds to local rain events through the spring and summer as shown by the short increases in lake level followed by a gradual decline in lake level which is driven by a combination of lake evaporation and the control of the lake outlet. Evaporation losses to Vancouver Island lakes and reservoirs are generally estimated to range between 300 and 600 mm during the summer months, depending on weather conditions each year. The small increases in the lake level shown on the graph are the responses to rainfall inputs, while the steady recession curve decline indicate the rate of loss of water from the lake due to all causes including Quamichan Creek, evaporation from the lake, and consumptive uses. Appendix B, Table 4 contains the list of current and pending water licenses assigned to Quamichan Lake.

The existing control is a relatively wide, flat channel that was constructed by excavation. If the full width of the channel was to be utilized to draw down the lake in the spring to serve the needs of the farmers, and then the outflow was restricted by some form of gate structure, it would be possible to control lake levels and stream flows to benefit both the farmers and the aquatic environment throughout the remainder of the summer.

Detailed hydrological modelling of the Quamichan Lake watershed is beyond the scope of this project. Such modelling would be useful in refining operational parameters of

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Quamichan Lake Outlet Control any control structure, and would be helpful in future efforts to understand water quality and contaminant mass concentration issues.

It is recommended that lake level monitoring and stream flow monitoring of lake discharge be commenced to support hydrological modelling and improve the understanding of the local water resource.

2.1.2 Survey of the Lake Outlet Channel The land survey of the lake outlet and the upper reach of Quamichan Creek were undertaken in July 2007 and are summarized as Appendix C.

The outlet channel was, at some time in the past, machine excavated into the weathered bedrock for at least 200 m with essentially no bed slope. The attached drawings and sections illustrate the general channel character.

The hydraulic control in Quamichan Creek that controls the lake level is variable depending on conditions. The slope of the creek channel is flat for at least 200 m. During low flow conditions, the lake level is governed by channel debris and obstructions such as the beaver dam in the reach from the lake outlet to the Water Survey of Canada (WSC) site – see section 3.1.2 . At moderately high flows, assuming no major obstruction in the channel like the beaver dam, the hydraulic control is simple channel capacity of the outlet reach. That capacity is governed by the channel dimensions and "roughness". At peak flows, and high lake water level, the break in channel slope about 300 m downstream or the channel capacity may govern the discharge rate. However, any large obstruction or significant debris could be the controlling feature and could move the control anywhere in the upstream reach from the footbridge to the downstream break in slope.

Currently, the beaver dam and associated debris is the lake level control under all conditions.

2.1.3 Control Structure Concept: With the exception of very high flows, the channel capacity of Quamichan Creek controls the lake drawdown and lake level at any time. If the lake outlet and channel discharge is maximized, the lake will draw down fairly rapidly to the elevation of the sill at the lake outlet. With no control structure this will serve the agricultural interests, but the creek will remain dry all summer, and lake water quality will suffer.

If a control structure is installed the lake drawdown can be managed in spring to serve farming needs. Once those needs are met the discharge can be reduced and water from spring and summer rainfall can be retained in the lake for other uses including maintaining creek flows. .

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A structure that does not reduce the maximum discharge, but can control lake levels during low flow periods is required to meet the management objectives.

There is no specific location for a control structure that provides significant hydraulic advantage. The structure must be located downstream of the existing footbridge since that location is the entrance of the creek channel from the lake as defined by the bedrock topography. A location immediately downstream of the footbridge is recommended since access from the cul-de-sac of Canary Place is convenient, and the structure and access to the structure is on land owned by the District of North Cowichan. In addition, the highest point in the creek is a short distance downstream from the proposed location. This will result in the structure being flooded on the upstream side for a greater portion of the year.

The control structure design criteria should:

• Utilize the full existing channel capacity to facilitate efficient spring draw down of the lake level. • Not restrict peak flows while the farmland is draining. Maintaining full flow to the minimum channel elevation has a very significant effect on the rate of discharge from the lake and therefore a very significant impact on upstream agriculture. • Provide discharge control at low flows. • Be a permanent structure. • Recognize that the structure is adjacent to a heavily used public park, and therefore must be designed for public safety and potential vandalism.

A proposed structure is sketched as Appendix A, Figure 5. The structure consists of a concrete flume with two control sections incorporated into the channel.

¾ The primary control section could be either a stop log weir or two large sliding gates. • The stop log design is shown as the least costly option. Stop logs are awkward to manage, subject to vandalism and require placement by at least two operators working in the water that represent a potential safety concern. • Sliding gates are more costly but are generally simpler to operate and somewhat less prone to damage by vandals. Debris jamming in the gates can be a maintenance problem.

The sliding gate option is recommended for the main control section.

¾ The small secondary control section would be a small sliding gate structure that is intended to provide relatively easy low flow control.

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• No provision for upstream fish passage during low flow operations has been made. This needs to be addressed in the context of the watershed management plan, which is beyond the scope of this study.

The control structure as sketched does not restrict the capacity of the channel. The problem with the existing channel is that it was dug "essentially flat" with the result that the channel capacity rather than the structure capacity is what controls the lake discharge. The channel capacity to discharge water at any time is directly related to how clear the channel is over the entire channel length. The current situation illustrates that any obstruction such as a beaver dam anywhere in the 300 m of the constructed channel will impact flow capacity and lake level.

The control structure would be fully opened at the end of the September to allow efficient passage of winter flows and, in spring, adjusted to lower the lake level to the maximum level that is acceptable and agreed to by the various stakeholders. The spring and summer flows and lake level would be controlled by closing the main control section and the discharge to Quamichan Creek would be regulated using the small sliding gate.

The structure incorporates a walkway with handrails for protection of both operators and the public, but it is not intended as a footbridge. Cast-in-place ladder rungs on both the upstream and downstream sides of the control structure provides access to the floor of the channel. It may be necessary to impede easy access by incorporating a locked chain or other gate.

2.1.4 Management of Beaver Activity:

Management of beaver activity is suggested by the use of a simple drainage structure based on the principle that the beavers tend not to plug drainage that is sub-surface. The inlet of the proposed beaver bypass is in a sump, upstream of the flume. This is not optimal, but it is the only option if the lake levels are to be held at relatively low levels. The drainage pipe is sloped upward so that the discharge end is higher than the inlet, ensuring that the inlet remains submerged and therefore not attractive to the beavers. The structure as drawn is shown in concrete. A less expensive alternative using the same principle could be constructed of corrugated steel pipe.

Installing a beaver baffle may not provide the necessary drainage due to the bedrock nature of the channel. In addition in Quamichan Creek, there is no specific location that attracts beavers, and therefore site-specific treatments are problematic since the animals may simply move on to a better location.

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Alternatives that have been used to try to manage beaver activity include: • Fencing along the stream banks and some distance upstream into the deeper water of the lake where a "practical dam" is not obvious to the animals, has been used with some success. Fencing for beaver control is at best uncertain, requires maintenance, is unsightly in a park setting, and is subject to vandalism and natural damage. Fencing may be considered but is not recommended as the first option. • Grating of structures has been used with some success although frequent inspection and clearing is required. The principal advantage of placing grates is that the animals build against the grate rather than in the structure, and if the grate is robust, it can be useful in clearing the debris by simply lifting the grate with machinery, and much of the debris structure is destroyed in the process. Grates are best used at sites where there is easy access to heavy equipment and where flooding can be tolerated. A grate is not recommended at the Quamichan Creek site. • "Beaver Beater" drains installed at existing beaver dams consist of a reverse graded pipe like that shown in the sketch for the proposed structure. If a beaver beater pipe were installed at an existing beaver dam in Quamichan Creek, it is likely that the beavers would simply create a new dam elsewhere. Beaver beaters work well in specific circumstances, but may not be effective in Quamichan Creek. • Removal of beaver dams can be a frustrating exercise, but should be done whenever possible before the lake or pond ecology adapts to the pond created by the dam. Removal should be accomplished in the same season as the dam is constructed.

It is recommended that the management of beaver activity in the area be considered as a long-term component of operations. It has been assumed that the animals will attempt to dam against the proposed control structure, and therefore an optional "Beaver Bypass" has been incorporated into the structure, but removal of beaver dams is likely to be a regular maintenance requirement. The beavers may exercise the option to locate their structure downstream of the control structure at any location, as they demonstrated recently by re-building a dam downstream of the site where their original structure was removed.

Management of the animals themselves is beyond the scope of this discussion and is therefore not recommended without consultation with wildlife management personnel. In some circumstances trapping of the animals is possible, but in this area it is unlikely to be effective or acceptable.

2.1.5 Management Regime of Lake Level and Creek Discharge The proposed control structure with the gates open provides the same discharge capacity of the existing channel. It is understood that without the impediment of the

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Management of the lake level requires clear criteria regarding the maximum and minimum lake levels at specific times, agreed to by the stakeholders. This can be expressed in the form of a table of levels and dates that provides targets for the operator of the structure. Fisheries management may require short-term release of higher flows to assist fish in migration. Such releases are not included in the following potential management schedule. Monitoring of the performance of the operations can be easily achieved by the placement of a compact data logger recording lake water level on a continuous basis.

Operations will require at least the following site visits:

Date Activity Sept 30 Opening of all structures to allow free and natural discharge, data logger download Nov. 15 Structure inspection debris removal as required Dec. 15 Structure inspection debris removal as required, data logger download Jan. 15 Structure inspection debris removal as required Feb. 15 Structure inspection debris removal as required Mar. 15 Structure inspection debris removal as required, data logger download April 15 Structure inspection, close the secondary control gate, check level relative to lake level management schedule. Primary gates may be fully closed at this time if appropriate April 21 Weekly structure inspection and review of control structure openings. through Primary gates should be fully closed by May 15 and all discharge June 15 directed through the secondary gate, data logger download mid June. June 15 Bi-weekly inspection and flow control adjustment through Sept 30 -Site experience will alter this schedule.

Responsibility for the operations and maintenance of the structure should be a local government agency. Volunteers, reporting to and submitting data and operational records to the agency, could do the actual operations and maintenance. This would provide long term stability both in term of maintenance funding and data retention. In addition, a local agency such as the District or Municipality has personnel, management expertise and equipment that may be required from time to time to support local efforts.

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2.1.6 Habitat Loss Footprint The proposed structure has a channel impact of approximately 6 m2, in the form of a concrete base flume at the same level as the existing channel. Since aquatic organisms will continue to utilize the area within the flume, the effective area of habitat loss is less than 6 m2.

2.1.7 Channel Maintenance Channel maintenance will be required to support operational control. Major structures including the beaver dam and the large debris such as the concrete well ring in the channel must be cleared to allow the channel to function. Minor woody debris, overhanging cover and the uneven profile of the channel base should be maintained for their habitat complexing value. Consultation with fisheries expertise may indicate opportunities to enhance channel habitat values with the construction of new and the enlargement of existing pools.

2.1.8 Monitoring Performance monitoring could be achieved by placing a water level data recorder in the inlet structure of the “Beaver Bypass”. The data could be of long term value in terms of monitoring changes in the watershed if a second data logger is used to re-activate Quamichan Creek WSC station. The relative costs of establishing these data collection sites would be limited to the instruments since the required costs for stilling wells is avoided.

It is recommended that these data collection stations be incorporated both to assist in project management and to provide valuable data in understanding the lake hydrology and water quality issues over time with changing land use and climate.

3. DISCUSSION

3.1 Lake Level Data

There are several sets of lake level measurements that have been collected over the years. The following notes describe and provide correlation between the data stations.

The elevation of each station has been referenced to geodetic coordinates based on a monument near the intersection of Indian Road and Swan Nest Drive. This is

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monument 69H3669, elevation 41.261 m ASL (Above Sea Level), data provided by the District of North Cowichan.

3.1.1 New Reference Mark As part of the work, a reference benchmark was established in a convenient public location for future reference. A 6 mm anchor bolt from which lake levels can be measured was placed in the retaining wall at Art Mann Park. The elevation of the top surface of the bolt is 26.194 m ASL (Above Sea Level). The details of the reference are provided as Appendix B, Figure 6.

3.1.2 Water Survey of Canada (WSC) station 08HA020 A lake level recording station was established by Environment Canada, and operated between 1980 to 1985 and 1990 to 1993 with data collection April through September. The station was discontinued in 1993. The data was collected and published relative to a local datum.

The station is accessible from Ryan Road crossing private property, and with the permission and assistance of the owner, the brass WSC benchmarks were located and surveyed relative to lake water level. Using an essentially simultaneous water level at the New Reference Mark, the adjustment factor was calculated to convert the published WSC lake level data into elevations relative to ASL. This adjusted data set of lake levels is included as Table 1.

Figure 7 provides the original WSC "Description of Station" card. Figure 9 illustrates the trend of lake level in graphical format, and Table 1 provides the WSC lake level data, adjusted to ASL to be consistent with other local data sets and the New Reference Mark.

The lake level data3 shows the lake level drops at a consistent rate through the data period. There does not appear to be any trend of average summer lake level increasing or decreasing with years in the period of record.

3.1.3 Stewart Data (6387 Lakes Road): A private water level site was established at the Stewart property and manual data records have been maintained for many years. The site was referenced to a benchmark in downtown Duncan. The site was correlated to the new reference mark by simultaneous reference to the lake water level and a minor index coefficient calculated

3 WSC data from: Environment Canada, HYDAT version 2004-2.04, release date 04/01/28 (most recent CD release, downloaded July 2007)

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to provide data comparison. This is an excellent data site established privately with considerable effort and care.

Appendix B, Table 3 contains the Stewart site data, converted to metric units and referenced to ASL datum.

3.1.4 Dr. David Groves Dr. Groves has collected some spot lake level data, referenced to the base of a steel stanchion along the wall at Art Mann Park. This data was not provided in time to be included in this report.

3.2 Quamichan Creek Flow

Quamichan Creek is the only surface discharge from the lake, although it is possible that sub-surface connections exist. This is possible but probably not likely considering the sandstone bedrock that appears at the surface along the west side of the lake, which appears to divide the Quamichan Lake from the lower and extensive Somenos Lake and wetlands. Any connection would be through fracture zones or permeable alluvial material. The seepage rate through such a connection would likely be small and is therefore considered of no significance.

3.2.1 Water Survey of Canada (WSC) station 08HA021 The outflow data set from Quamichan Lake is based on a site approximately 135 m downstream from the failing footbridge at the outlet of Quamichan Lake. The site is currently in the excavated creek channel. The site was operated discontinuously from 1954 through 1997, but it is not clear when the current site with the stilling well for stage recording was established. There are two full years of data (1996, 1997) and continuous data April through September for 6 additional years. The site data is shown in chart form as Appendix B, Figure 10. The data is available from the WSC4 HYDAT CD or by contacting the author. The creek hydrographs clearly show that flow in the creek depends entirely on the lake.

3.3 Channel Capacity

The channel capacity is the ability of the channel to carry flow and described as a relationship between the water level and the flow rate. The width, depth, cross section

4 WSC data from: Environment Canada, HYDAT version 2004-2.04, release date 04/01/28 (most recent CD release, downloaded July 2007)

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Quamichan Creek channel capacity has been defined empirically by the flow measurements at the WSC station on the creek. Bank full flow is about 2 m3/s during peak flow events. This flow rate is exceeded during brief periods during extreme storms, at which time flooding occurs.

Quamichan Creek channel is an excavated channel in bedrock of moderate roughness, adequate cross section on average but with little bed slope. Local "choke points of debris, most notably the beaver dam, have the dominant impact on the system capacity.

Improvements in channel can be achieved by reducing roughness by channel cleaning and shaping, or by increasing the channel dimensions or the bed slope.

The channel capacity is discussed in Appendix D.

It is recommended that local flow restrictions such the beaver dam and some debris be removed from the channel to improve the channel capacity and lower water levels.

4. DEVELOPING STORAGE FOR FISH ENHANCEMENT

The suggestion has been made that the storage be developed for enhancement of fish values, to maintain flow in Quamichan Creek during the summer and to provide flow pulses to encourage migration of Coho smolts. Since a management plan has not been developed for the watershed, it is premature to design for this option. The following comments are for discussion only.

There are three options that can be considered: ¾ Negative Storage ¾ Positive Storage ¾ Active Management

"Negative Storage" is the use of storage volume below the existing minimum lake discharge elevation. Lowering the creek elevation by some 10 to 30 cm and using the control structure to lower the lake level rapidly to "normal" late spring levels to serve agricultural interests would retain stored water below the "normal" level. Managing the release of this stored water "for fish" could be beneficial.

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This approach is based on lowering the "normal" early summer lake level below typical historical levels and further lowering the late summer levels by actively lowering the lake sill. This could only be achieved by extensive channel impacts and rock excavation.

“Positive Storage" is where the winter water is held back and typically involves a dam or weir that raises the lake water level as the existing beaver dam has done. This is not considered to be an option because of the negative impacts to agriculture and property infrastructure.

"Active Management" involves cleaning the existing channel to maximize the rate and level that the lake can be drawn down and installing a control structure. Hand clearing is the preferred method of channel clearing since it reduces impacts, but a small machine could be effectively used if the impacts of this approach are acceptable to private property owners and the agencies. • Rapid drawdown in spring will accommodate agricultural interests • No new storage is developed by actively lowering the creek channel • Once the spring low water level target is met, discharge is controlled and the lake is held at normal historical levels. The lake level is allowed to rise in response to early summer precipitation since active draining of farm lands will have been accomplished. A high degree of cooperation will be required between the farm interests and the environmental / fisheries interests.

5. CONCLUSION AND RECOMMENDATIONS

• The beaver dam is responsible for maintaining the high lake levels that delay access to farmland and place shoreline facilities at risk. The dam does not improve or increase habitat for beavers and the removal of the dam will not directly harm the beavers. It is therefore recommended that the beaver dam be removed, with other obstructions and larger debris. Management of the animals is beyond the scope of this study.

• The management of the beaver activity will be an on-going challenge since it is likely regular debris removal from beaver activities around the lake, and beaver dam removal may be regularly required. The flow along the channel needs to be monitored once the obstructions have been removed, and "choke" points identified for hand removal of obstructions. Removal of these obstructions on a regular basis is preferred to wholesale machine clearing of the channel.

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• A control structure at the upstream end of Quamichan Creek can be constructed on land owned by the District of North Cowichan. Good access to the structure without crossing private property is available from Canary Place. The structure can provide the control to operate the lake levels in a manner that will assist in reducing the conflicts between local stakeholders. There is no significant advantage to locating the structure further downstream. It is recommended that the concrete flume structure with sliding gates be constructed to manage the lake discharge.

• Operation and maintenance of the control structure should be the responsibility of a local government agency in cooperation with the local Stewardship committee.

• Channel maintenance will need to be part of the operational activities of any management activity. The water license for the structure should include provision for channel maintenance and clearing. Environmental concerns associated with such maintenance will have to be addressed, and as a result it is recommended that maintenance activities should be executed in a manner that maintains some channel complexity and roughness to support riparian values while balancing hydraulic efficiency.

• It is recommended that long term monitoring of both the lake level and creek discharge is re-instated. This data collection will verify operations management and will provide valuable information that will contribute to the understanding of the lake water quality and hydrology.

These recommendations are based on providing lake levels that were historically experienced within the last several decades, with the lake served by the existing but clear channel.

6. DISCLAIMER

This report was prepared by D.G.V. Engineering Services Ltd. for the account of Friends of Quamichan Lake Stewardship Committee. The material in it reflects the best judgment of D.G.V. Engineering Services Ltd. and Mr. D. Vincent, P. Eng. in light of the information available at the time of preparation. Any use which a third party makes of this report, or any reliance on or decisions to be made based on it, are the responsibility of such third parties. D.G.V. Engineering Services Ltd. accepts no responsibility for damages, if any, suffered by any third party as a result of decisions made or actions based on this report.

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7. CERTIFICATION

This report was respectfully submitted to Friends of Quamichan Lake Stewardship Committee by D.G.V. Engineering Services Ltd.

David Vincent, P. Eng.

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8. ATTACHMENTS

APPENDIX A

Figure 1 Drawing 9073-CW-01: General Location Map Figure 2 NTS 92B/13 E: Topographic Map - Quamichan Lake General Area Figure 3 Fish and Wildlife Drawing: “Quamichan Lake” – Bathymetry Figure 4 Drawing 9073-CW-02: Quamichan Lake outlet Plan and Sections - 3 sheets Figure 5 Drawing 9073-CW-03: Proposed Water Level Control Structure – 2 sheets

APPENDIX B

Figure 6 Site Data Sheet: New Reference mark - Lake Levels Figure 7 WSC Site Data Sheet: Quamichan Lake Level Station Description Figure 8 WSC Site Data Sheet: Quamichan Creek Flow Station Description Figure 9 WSC Chart: “Quamichan Lake Levels” Chart 1960-1993 data Figure 10 WSC Chart: “Quamichan Creek at the Outlet of Quamichan Lake - 08HA021” WSC Chart 1954-1997 data

Table1 WSC Lake Level Data, Station 08HA020 (1980-1993) Table 2 Duncan Bay Climate Data: Environment Canada Canadian Climate Normals 1971-2000 Table 3 Gaylord Stewart Stage Data: “Quamichan Lake Water Levels” Summary 1988-2007 Table 4 Water Licence Table: “Water Licences Report” Quamichan Lake – current and pending

APPENDIX C Survey Detail

APPENDIX D Channel Capacity

4-Feb-08 D.G.V. Engineering Services Ltd. 17 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

APPENDIX A

Figure 1 Drawing 9073-CW-01: General Location Map

Figure 2 NTS 92B/13 E: Topographic Map - Quamichan Lake General Area

Figure 3 Fish and Wildlife Drawing: “Quamichan Lake” – Bathymetry

Figure 4 Drawing 9073-CW-02: Quamichan Lake outlet Plan and Sections - 3 sheets

Figure 5 Drawing 9073-CW-03: Proposed Water Level Control Structure – 2 sheets

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Figure 1

Drawing 9073-CW-01: General Location Map

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Figure 2

NTS 92B/13 E: Topographic Map - Quamichan Lake General Area

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Figure 2: Topographic Map of Quamichan Lake Watershed Ref: NTS 92B/13E Softmap Plus Quamichan Lake Outlet Control

Figure 3

Fish and Wildlife Drawing: “Quamichan Lake” – Bathymetry

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Figure 4

Drawing 9073-CW-02: Quamichan Lake outlet Plan and Sections - 3 sheets

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Figure 5

Drawing 9073-CW-03: Proposed Water Level Control Structure – 2 sheets

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

APPENDIX B

Figure 6 Site Data Sheet: New Reference mark - Lake Levels

Figure 7 WSC Site Data Sheet: Quamichan Lake Level Station Description

Figure 8 WSC Site Data Sheet: Quamichan Creek Flow Station Description

Figure 9 WSC Chart: “Quamichan Lake Levels” Chart 1960-1993 data

Figure 10 WSC Chart: “Quamichan Creek at the Outlet of Quamichan Lake - 08HA021” WSC Chart 1954-1997 data

Table1 WSC Lake Level Data, Station 08HA020 (1980-1993)

Table 2 Duncan Bay Climate Data: Environment Canada Canadian Climate Normals 1971-2000

Table 3 Gaylord Stewart Stage Data: “Quamichan Lake Water Levels” Summary 1988-2007

Table 4 Water Licence Table: “Water Licences Report” Quamichan Lake – current and pending

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Figure 6

Site Data Sheet: New Reference mark - Lake Levels

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

SITE DATA SHEET Site Information SITE 9073-CW Site: Quamichan Lake Data Collection Type: water level UTM co-ordinates (NAD83): 10 U 450 707 E 5 404 122 N Location: Art Mann Park, on Quamichan Lake, east of Duncan bolt through tag 4428 drilled into concrete ~150 below top of curb, next to 7th Benchmark(s): upright bracket footing east of the boat ramp at Art Mann Park 26.194 ASL; tied to monument 69H3669 on Indian Road, just north of Swan's Elevation reference: Nest Drive ACCESS INFORMATION Property Owner: public property Access Requirements: park closed dusk to dawn Hazards and Special Instructions: none LOCATION SKETCH

WATER LEVELS STAGE DATE TIME FB REF WL (m) COMMENTS 25-Jul-07 8:20 53-93 -0.534 25.660 bolt installation on tag DGV4428 6-Aug-07 8:00 53-103 -0.590 25.604 8-Aug-07 8:30 70-1 -0.602 25.592

Site Data Sheet.xls D.G.V. Engineering Services Ltd. 8-08-07 Nanaimo BC Quamichan Lake Outlet Control

Figure 7

WSC Site Data Sheet: Quamichan Lake Level Station Description

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Figure 8

WSC Site Data Sheet: Quamichan Creek Flow Station Description

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Figure 9

WSC Chart: “Quamichan Lake Levels” Chart 1960-1993 data

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Levels 1980 1981 1982 1983 1984 1985 1990 1991 1992 1993 26

25.5 Lake Level (m) ASL 25

24.5 1-Apr 21-Apr 11-May 31-May 20-Jun 10-Jul 30-Jul 19-Aug 8-Sep 28-Sep Date Quamichan Lake Outlet Control

Figure 10

WSC Chart: “Quamichan Creek at the Outlet of Quamichan Lake - 08HA021” WSC Chart 1954-1997 data

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Creek at the Outlet of Quamichan Lake - 08HA021

2.5

2

1954 1955 1.5 1956 1971 1990 1991 1992

Flow (cms) 1993 1994 1 1995 1996 1997

0.5

0 1-Jan 20-Feb 10-Apr 30-May 19-Jul 7-Sep 27-Oct 16-Dec Date Quamichan Lake Outlet Control

Table1

WSC Lake Level Data, Station 08HA020 (1980-1993)

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Water levels - Datum adjusted to ASL Station Discontinued

ID PARAM TYPE Year DD Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 08HA020 2 8 1980 1 25.809 25.627 25.499 25.457 25.345 25.237 08HA020 2 8 1980 2 25.801 25.625 25.495 25.455 25.341 25.235 08HA020 2 8 1980 3 25.787 25.621 25.495 25.461 25.335 25.233 08HA020 2 8 1980 4 25.777 25.621 25.495 25.465 25.327 25.233 08HA020 2 8 1980 5 25.771 25.609 25.493 25.465 25.327 25.231 08HA020 2 8 1980 6 25.767 25.598 25.489 25.463 25.321 25.227 08HA020 2 8 1980 7 25.761 25.587 25.485 25.459 25.319 25.225 08HA020 2 8 1980 8 25.751 25.581 25.505 25.451 25.313 25.223 08HA020 2 8 1980 9 25.759 25.587 25.517 25.445 25.307 25.221 08HA020 2 8 1980 10 25.753 25.585 25.515 25.445 25.305 25.217 08HA020 2 8 1980 11 25.745 25.575 25.511 25.443 25.301 25.217 08HA020 2 8 1980 12 25.735 25.571 25.505 25.439 25.297 25.215 08HA020 2 8 1980 13 25.731 25.565 25.501 25.435 25.291 25.213 08HA020 2 8 1980 14 25.723 25.561 25.499 25.433 25.287 25.211 25.173 08HA020 2 8 1980 15 25.731 25.555 25.495 25.427 25.285 25.207 08HA020 2 8 1980 16 25.725 25.547 25.491 25.425 25.279 25.205 08HA020 2 8 1980 17 25.719 25.545 25.488 25.421 25.271 25.203 08HA020 2 8 1980 18 25.715 25.541 25.485 25.417 25.277 25.203 08HA020 2 8 1980 19 25.721 25.535 25.485 25.415 25.275 25.201 08HA020 2 8 1980 20 25.715 25.539 25.479 25.411 25.271 25.199 08HA020 2 8 1980 21 25.709 25.529 25.469 25.405 25.267 25.199 08HA020 2 8 1980 22 25.703 25.525 25.465 25.401 25.265 25.197 08HA020 2 8 1980 23 25.685 25.529 25.459 25.395 25.263 25.197 08HA020 2 8 1980 24 25.679 25.519 25.455 25.391 25.255 25.197 08HA020 2 8 1980 25 25.863 25.675 25.517 25.485 25.386 25.253 25.195 08HA020 2 8 1980 26 25.671 25.515 25.485 25.378 25.253 25.195 08HA020 2 8 1980 27 25.665 25.519 25.479 25.371 25.251 25.193 08HA020 2 8 1980 28 25.655 25.517 25.475 25.368 25.247 25.191 08HA020 2 8 1980 29 25.649 25.515 25.473 25.357 25.245 25.187 08HA020 2 8 1980 30 25.641 25.511 25.455 25.351 25.243 25.186 08HA020 2 8 1980 31 25.507 25.347 25.239 08HA020 2 8 1981 1 25.649 25.571 25.467 25.393 25.254 25.116 08HA020 2 8 1981 2 25.649 25.57 25.453 25.391 25.248 25.114 08HA020 2 8 1981 3 25.647 25.569 25.449 25.385 25.244 25.112 08HA020 2 8 1981 4 25.647 25.569 25.447 25.379 25.238 25.108 08HA020 2 8 1981 5 25.645 25.567 25.445 25.23 25.108 08HA020 2 8 1981 6 25.645 25.565 25.449 25.366 25.228 25.106 08HA020 2 8 1981 7 25.639 25.565 25.447 25.358 25.224 25.108 08HA020 2 8 1981 8 25.635 25.557 25.445 25.336 25.22 25.11

Water Survey of Canada Station 08HA029 1 Quamichan Lake Water levels - Datum adjusted to ASL Station Discontinued

ID PARAM TYPE Year DD Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 08HA020 2 8 1981 9 25.629 25.555 25.451 25.332 25.216 25.112 08HA020 2 8 1981 10 25.625 25.549 25.449 25.328 25.212 25.112 08HA020 2 8 1981 11 25.623 25.549 25.447 25.326 25.208 25.108 08HA020 2 8 1981 12 25.625 25.537 25.445 25.325 25.206 25.106 08HA020 2 8 1981 13 25.627 25.529 25.435 25.324 25.197 25.098 08HA020 2 8 1981 14 25.625 25.529 25.433 25.32 25.192 25.096 08HA020 2 8 1981 15 25.625 25.525 25.431 25.318 25.188 25.092 08HA020 2 8 1981 16 25.625 25.521 25.429 25.316 25.186 25.085 08HA020 2 8 1981 17 25.621 25.515 25.433 25.314 25.183 25.086 08HA020 2 8 1981 18 25.615 25.507 25.433 25.312 25.178 25.082 08HA020 2 8 1981 19 25.717 25.613 25.506 25.435 25.308 25.176 25.078 08HA020 2 8 1981 20 25.613 25.505 25.431 25.304 25.172 25.077 08HA020 2 8 1981 21 25.609 25.503 25.429 25.298 25.168 25.074 08HA020 2 8 1981 22 25.605 25.499 25.425 25.296 25.162 25.078 08HA020 2 8 1981 23 25.599 25.497 25.425 25.292 25.158 25.08 08HA020 2 8 1981 24 25.595 25.495 25.423 25.29 25.155 25.082 08HA020 2 8 1981 25 25.591 25.493 25.417 25.286 25.148 25.088 08HA020 2 8 1981 26 25.585 25.491 25.415 25.278 25.144 25.09 08HA020 2 8 1981 27 25.579 25.489 25.411 25.276 25.14 25.098 08HA020 2 8 1981 28 25.581 25.485 25.405 25.272 25.136 25.104 08HA020 2 8 1981 29 25.577 25.483 25.401 25.268 25.128 25.112 08HA020 2 8 1981 30 25.581 25.479 25.395 25.26 25.116 25.116 08HA020 2 8 1981 31 25.475 25.258 25.118 08HA020 2 8 1982 1 25.709 25.593 25.443 25.302 25.172 25.133 08HA020 2 8 1982 2 25.707 25.585 25.447 25.298 25.172 25.133 08HA020 2 8 1982 3 25.709 25.583 25.439 25.294 25.171 25.125 08HA020 2 8 1982 4 25.705 25.573 25.435 25.29 25.17 25.075 08HA020 2 8 1982 5 25.703 25.565 25.425 25.286 25.17 25.075 08HA020 2 8 1982 6 25.701 25.559 25.417 25.278 25.169 25.045 08HA020 2 8 1982 7 25.699 25.555 25.41 25.27 25.169 25.045 08HA020 2 8 1982 8 25.697 25.551 25.395 25.263 25.169 25.044 08HA020 2 8 1982 9 25.689 25.545 25.255 25.168 25.044 08HA020 2 8 1982 10 25.685 25.537 25.371 25.244 25.155 25.043 08HA020 2 8 1982 11 25.675 25.529 25.365 25.237 25.152 25.043 08HA020 2 8 1982 12 25.673 25.523 25.359 25.235 25.149 25.042 08HA020 2 8 1982 13 25.671 25.515 25.355 25.234 25.149 25.042 08HA020 2 8 1982 14 25.679 25.509 25.351 25.233 25.147 25.041 08HA020 2 8 1982 15 25.675 25.503 25.345 25.231 25.145 08HA020 2 8 1982 16 25.673 25.499 25.339 25.229 25.145

Water Survey of Canada Station 08HA029 2 Quamichan Lake Water levels - Datum adjusted to ASL Station Discontinued

ID PARAM TYPE Year DD Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 08HA020 2 8 1982 17 25.669 25.495 25.327 25.229 25.145 08HA020 2 8 1982 18 25.667 25.491 25.321 25.228 25.145 08HA020 2 8 1982 19 25.665 25.489 25.315 25.228 25.145 08HA020 2 8 1982 20 25.659 25.485 25.313 25.227 25.145 08HA020 2 8 1982 21 25.651 25.483 25.311 25.225 25.145 08HA020 2 8 1982 22 25.643 25.481 25.307 25.221 25.144 08HA020 2 8 1982 23 25.639 25.473 25.305 25.217 25.144 08HA020 2 8 1982 24 25.635 25.467 25.303 25.215 25.142 08HA020 2 8 1982 25 25.631 25.463 25.299 25.207 25.142 08HA020 2 8 1982 26 25.625 25.465 25.295 25.205 25.142 08HA020 2 8 1982 27 25.619 25.459 25.303 25.202 25.141 08HA020 2 8 1982 28 25.611 25.455 25.305 25.202 25.141 08HA020 2 8 1982 29 25.711 25.599 25.451 25.307 25.196 25.14 08HA020 2 8 1982 30 25.708 25.595 25.447 25.305 25.176 25.14 08HA020 2 8 1982 31 25.445 25.175 25.135 08HA020 2 8 1983 1 25.851 25.607 25.423 25.309 25.207 25.142 08HA020 2 8 1983 2 25.855 25.595 25.421 25.305 25.203 25.142 08HA020 2 8 1983 3 25.847 25.587 25.415 25.303 25.199 25.141 08HA020 2 8 1983 4 25.839 25.581 25.41 25.301 25.193 25.141 08HA020 2 8 1983 5 25.831 25.575 25.407 25.299 25.19 25.14 08HA020 2 8 1983 6 25.825 25.571 25.405 25.297 25.188 25.138 08HA020 2 8 1983 7 25.801 25.565 25.4 25.295 25.186 25.144 08HA020 2 8 1983 8 25.793 25.557 25.397 25.293 25.184 25.161 08HA020 2 8 1983 9 25.785 25.553 25.391 25.289 25.182 25.213 08HA020 2 8 1983 10 25.779 25.549 25.387 25.29 25.18 25.263 08HA020 2 8 1983 11 25.773 25.545 25.383 25.291 25.178 25.257 08HA020 2 8 1983 12 25.767 25.539 25.379 25.293 25.176 25.253 08HA020 2 8 1983 13 25.759 25.535 25.373 25.288 25.172 25.251 08HA020 2 8 1983 14 25.745 25.531 25.369 25.286 25.156 25.247 08HA020 2 8 1983 15 25.727 25.527 25.365 25.284 25.144 25.245 08HA020 2 8 1983 16 25.715 25.523 25.361 25.282 25.139 25.243 08HA020 2 8 1983 17 25.711 25.515 25.357 25.28 25.133 25.239 08HA020 2 8 1983 18 25.705 25.512 25.355 25.276 25.127 25.226 08HA020 2 8 1983 19 25.695 25.509 25.353 25.272 25.123 25.219 08HA020 2 8 1983 20 25.683 25.505 25.348 25.268 25.119 25.208 08HA020 2 8 1983 21 25.973 25.675 25.501 25.348 25.262 25.115 25.193 08HA020 2 8 1983 22 25.671 25.495 25.344 25.258 25.113 25.173 08HA020 2 8 1983 23 25.657 25.491 25.338 25.254 25.111 25.153 08HA020 2 8 1983 24 25.651 25.471 25.338 25.247 25.109 25.148

Water Survey of Canada Station 08HA029 3 Quamichan Lake Water levels - Datum adjusted to ASL Station Discontinued

ID PARAM TYPE Year DD Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 08HA020 2 8 1983 25 25.645 25.465 25.334 25.243 25.107 25.142 08HA020 2 8 1983 26 25.639 25.459 25.33 25.241 25.109 25.14 08HA020 2 8 1983 27 25.633 25.451 25.328 25.237 25.111 25.185 08HA020 2 8 1983 28 25.631 25.445 25.324 25.231 25.112 25.179 08HA020 2 8 1983 29 25.625 25.439 25.316 25.227 25.113 25.147 08HA020 2 8 1983 30 25.621 25.43 25.31 25.221 25.11 25.133 08HA020 2 8 1983 31 25.425 25.217 25.108 08HA020 2 8 1984 1 25.811 25.645 25.619 25.452 25.268 25.136 08HA020 2 8 1984 2 25.809 25.675 25.611 25.446 25.26 25.128 08HA020 2 8 1984 3 25.805 25.671 25.607 25.442 25.252 25.124 08HA020 2 8 1984 4 25.805 25.665 25.607 25.438 25.244 25.124 08HA020 2 8 1984 5 25.803 25.663 25.605 25.43 25.24 25.13 08HA020 2 8 1984 6 25.795 25.659 25.599 25.422 25.238 25.138 08HA020 2 8 1984 7 25.785 25.647 25.597 25.418 25.228 25.136 08HA020 2 8 1984 8 25.855 25.775 25.647 25.595 25.416 25.226 25.133 08HA020 2 8 1984 9 25.765 25.645 25.587 25.408 25.222 25.13 08HA020 2 8 1984 10 25.755 25.639 25.583 25.398 25.218 25.128 08HA020 2 8 1984 11 25.753 25.643 25.577 25.394 25.216 25.128 08HA020 2 8 1984 12 25.755 25.641 25.573 25.386 25.214 25.126 08HA020 2 8 1984 13 25.757 25.645 25.565 25.382 25.208 25.13 08HA020 2 8 1984 14 25.754 25.645 25.556 25.377 25.202 25.13 08HA020 2 8 1984 15 25.737 25.645 25.548 25.374 25.196 25.126 08HA020 2 8 1984 16 25.731 25.641 25.542 25.37 25.19 25.122 08HA020 2 8 1984 17 25.715 25.633 25.53 25.362 25.186 25.118 08HA020 2 8 1984 18 25.713 25.629 25.518 25.357 25.182 25.117 08HA020 2 8 1984 19 25.713 25.631 25.512 25.348 25.192 25.116 08HA020 2 8 1984 20 25.704 25.629 25.512 25.342 25.188 25.118 08HA020 2 8 1984 21 25.695 25.625 25.506 25.36 25.18 25.12 08HA020 2 8 1984 22 25.691 25.625 25.5 25.328 25.176 25.118 08HA020 2 8 1984 23 25.687 25.623 25.492 25.324 25.168 25.11 08HA020 2 8 1984 24 25.683 25.625 25.488 25.318 25.16 25.104 08HA020 2 8 1984 25 25.671 25.629 25.476 25.31 25.154 25.1 08HA020 2 8 1984 26 25.664 25.645 25.472 25.3 25.158 25.098 08HA020 2 8 1984 27 25.645 25.645 25.47 25.296 25.158 25.096 08HA020 2 8 1984 28 25.639 25.641 25.466 25.292 25.152 25.096 08HA020 2 8 1984 29 25.634 25.639 25.462 25.286 25.146 25.094 08HA020 2 8 1984 30 25.637 25.625 25.456 25.282 25.142 25.093 08HA020 2 8 1984 31 25.625 25.276 25.138 08HA020 2 8 1985 1 25.715 25.555 25.46 25.335 25.18 25.026

Water Survey of Canada Station 08HA029 4 Quamichan Lake Water levels - Datum adjusted to ASL Station Discontinued

ID PARAM TYPE Year DD Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 08HA020 2 8 1985 2 25.715 25.555 25.455 25.315 25.175 25.021 08HA020 2 8 1985 3 25.725 25.555 25.455 25.315 25.17 25.021 08HA020 2 8 1985 4 25.735 25.555 25.455 25.315 25.155 25.016 08HA020 2 8 1985 5 25.725 25.545 25.445 25.295 25.155 25.016 08HA020 2 8 1985 6 25.725 25.545 25.45 25.265 25.145 25.016 08HA020 2 8 1985 7 25.715 25.545 25.45 25.255 25.145 25.011 08HA020 2 8 1985 8 25.715 25.545 25.445 25.255 25.135 25.011 25.065 08HA020 2 8 1985 9 25.705 25.545 25.435 25.245 25.135 25.006 08HA020 2 8 1985 10 25.704 25.535 25.43 25.245 25.13 25.016 08HA020 2 8 1985 11 25.695 25.535 25.425 25.24 25.125 25.016 08HA020 2 8 1985 12 25.686 25.535 25.42 25.238 25.125 25.011 08HA020 2 8 1985 13 25.675 25.535 25.418 25.238 25.12 25.011 08HA020 2 8 1985 14 25.666 25.535 25.415 25.235 25.12 25.006 08HA020 2 8 1985 15 25.655 25.535 25.414 25.23 25.11 25.006 08HA020 2 8 1985 16 25.655 25.525 25.414 25.23 25.085 25.001 08HA020 2 8 1985 17 25.655 25.515 25.414 25.225 25.055 25.001 08HA020 2 8 1985 18 25.645 25.515 25.41 25.225 25.035 24.996 08HA020 2 8 1985 19 25.645 25.505 25.405 25.223 25.03 24.996 08HA020 2 8 1985 20 25.645 25.646 25.505 25.385 25.215 25.028 24.996 08HA020 2 8 1985 21 25.644 25.505 25.21 25.028 24.991 08HA020 2 8 1985 22 25.636 25.505 25.365 25.21 25.028 24.991 08HA020 2 8 1985 23 25.63 25.515 25.36 25.21 25.027 24.991 08HA020 2 8 1985 24 25.623 25.505 25.36 25.21 25.027 24.991 08HA020 2 8 1985 25 25.614 25.505 25.36 25.205 25.027 24.986 08HA020 2 8 1985 26 25.603 25.485 25.355 25.205 25.026 24.986 08HA020 2 8 1985 27 25.595 25.465 25.355 25.2 25.026 24.986 08HA020 2 8 1985 28 25.586 25.464 25.35 25.2 25.026 24.981 08HA020 2 8 1985 29 25.575 25.475 25.35 25.2 25.027 24.986 08HA020 2 8 1985 30 25.566 25.475 25.345 25.195 25.026 24.986 08HA020 2 8 1985 31 25.46 25.19 25.026 08HA020 2 8 1990 1 25.766 25.663 25.557 25.486 25.303 25.143 08HA020 2 8 1990 2 25.761 25.656 25.556 25.472 25.299 25.144 08HA020 2 8 1990 3 25.756 25.66 25.561 25.462 25.292 25.144 08HA020 2 8 1990 4 25.756 25.659 25.561 25.46 25.285 25.144 08HA020 2 8 1990 5 25.751 25.648 25.561 25.457 25.277 25.164 08HA020 2 8 1990 6 25.751 25.634 25.561 25.457 25.273 25.164 08HA020 2 8 1990 7 25.751 25.624 25.563 25.442 25.267 25.164 08HA020 2 8 1990 8 25.746 25.614 25.562 25.442 25.261 25.164 08HA020 2 8 1990 9 25.741 25.604 25.563 25.437 25.261 25.164

Water Survey of Canada Station 08HA029 5 Quamichan Lake Water levels - Datum adjusted to ASL Station Discontinued

ID PARAM TYPE Year DD Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 08HA020 2 8 1990 10 25.741 25.599 25.563 25.427 25.235 25.164 08HA020 2 8 1990 11 25.736 25.584 25.562 25.422 25.213 25.154 08HA020 2 8 1990 12 25.725 25.584 25.561 25.412 25.193 25.154 08HA020 2 8 1990 13 25.715 25.584 25.555 25.407 25.193 25.154 08HA020 2 8 1990 14 25.71 25.579 25.553 25.403 25.183 25.154 08HA020 2 8 1990 15 25.667 25.574 25.549 25.403 25.183 25.144 08HA020 2 8 1990 16 25.666 25.574 25.545 25.403 25.163 25.134 08HA020 2 8 1990 17 25.665 25.564 25.54 25.383 25.163 25.134 08HA020 2 8 1990 18 25.663 25.564 25.535 25.383 25.173 25.134 08HA020 2 8 1990 19 25.663 25.564 25.531 25.373 25.193 25.134 08HA020 2 8 1990 20 25.662 25.563 25.526 25.373 25.193 25.134 08HA020 2 8 1990 21 25.662 25.564 25.525 25.368 25.183 25.134 08HA020 2 8 1990 22 25.663 25.562 25.523 25.36 25.183 25.134 08HA020 2 8 1990 23 25.663 25.561 25.522 25.355 25.183 25.134 08HA020 2 8 1990 24 25.661 25.56 25.52 25.349 25.173 25.134 08HA020 2 8 1990 25 25.662 25.56 25.518 25.343 25.163 25.132 08HA020 2 8 1990 26 25.663 25.559 25.515 25.337 25.143 25.134 08HA020 2 8 1990 27 25.663 25.558 25.511 25.333 25.143 25.124 08HA020 2 8 1990 28 25.665 25.557 25.507 25.327 25.123 25.124 08HA020 2 8 1990 29 25.665 25.557 25.502 25.321 25.123 25.124 08HA020 2 8 1990 30 25.663 25.556 25.496 25.314 25.123 25.114 08HA020 2 8 1990 31 25.556 25.309 25.163 08HA020 2 8 1991 1 25.802 25.712 25.522 25.395 25.265 25.275 08HA020 2 8 1991 2 25.802 25.705 25.516 25.389 25.264 25.277 08HA020 2 8 1991 3 25.802 25.705 25.506 25.382 25.261 25.278 08HA020 2 8 1991 4 25.814 25.682 25.502 25.261 25.275 25.203 08HA020 2 8 1991 5 25.832 25.686 25.506 25.261 25.275 08HA020 2 8 1991 6 25.846 25.692 25.495 25.255 25.272 08HA020 2 8 1991 7 25.926 25.676 25.482 25.355 25.244 25.268 08HA020 2 8 1991 8 25.915 25.672 25.476 25.355 25.234 25.265 08HA020 2 8 1991 9 25.915 25.665 25.469 25.344 25.236 25.264 08HA020 2 8 1991 10 25.902 25.656 25.462 25.335 25.238 25.262 08HA020 2 8 1991 11 25.888 25.646 25.466 25.331 25.245 25.261 08HA020 2 8 1991 12 25.891 25.639 25.459 25.335 25.244 25.258 08HA020 2 8 1991 13 25.876 25.632 25.452 25.325 25.241 25.255 08HA020 2 8 1991 14 25.859 25.629 25.446 25.325 25.238 25.251 08HA020 2 8 1991 15 25.846 25.622 25.446 25.324 25.235 25.248 08HA020 2 8 1991 16 25.837 25.616 25.452 25.318 25.234 25.248 08HA020 2 8 1991 17 25.826 25.619 25.445 25.315 25.228 25.245

Water Survey of Canada Station 08HA029 6 Quamichan Lake Water levels - Datum adjusted to ASL Station Discontinued

ID PARAM TYPE Year DD Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 08HA020 2 8 1991 18 25.815 25.596 25.439 25.315 25.224 25.244 08HA020 2 8 1991 19 25.806 25.586 25.439 25.304 25.218 25.241 08HA020 2 8 1991 20 25.806 25.586 25.432 25.304 25.215 25.238 08HA020 2 8 1991 21 25.792 25.579 25.432 25.304 25.214 25.235 08HA020 2 8 1991 22 25.776 25.576 25.435 25.295 25.209 25.231 08HA020 2 8 1991 23 25.765 25.566 25.426 25.295 25.204 25.228 08HA020 2 8 1991 24 25.765 25.565 25.426 25.298 25.201 25.225 08HA020 2 8 1991 25 25.752 25.562 25.425 25.295 25.191 25.224 08HA020 2 8 1991 26 25.746 25.549 25.419 25.294 25.191 25.224 08HA020 2 8 1991 27 25.735 25.546 25.416 25.291 25.194 25.224 08HA020 2 8 1991 28 25.736 25.544 25.415 25.281 25.195 25.224 08HA020 2 8 1991 29 25.726 25.539 25.415 25.284 25.228 25.218 08HA020 2 8 1991 30 25.719 25.536 25.396 25.281 25.278 25.215 08HA020 2 8 1991 31 25.529 25.281 25.275 08HA020 2 8 1992 1 25.644 25.604 25.429 25.308 25.247 25.132 08HA020 2 8 1992 2 25.64 25.601 25.419 25.294 25.243 25.129 25.075 08HA020 2 8 1992 3 25.632 25.6 25.413 25.294 25.237 25.126 08HA020 2 8 1992 4 25.625 25.597 25.406 25.288 25.233 25.119 08HA020 2 8 1992 5 25.618 25.594 25.399 25.307 25.23 25.115 08HA020 2 8 1992 6 25.611 25.591 25.389 25.307 25.227 25.109 08HA020 2 8 1992 7 25.602 25.591 25.385 25.308 25.22 25.109 08HA020 2 8 1992 8 25.595 25.571 25.378 25.308 25.223 25.108 08HA020 2 8 1992 9 25.592 25.561 25.307 25.223 25.106 08HA020 2 8 1992 10 25.582 25.556 25.372 25.314 25.217 25.106 08HA020 2 8 1992 11 25.585 25.553 25.369 25.311 25.216 25.106 08HA020 2 8 1992 12 25.572 25.55 25.369 25.307 25.213 25.106 08HA020 2 8 1992 13 25.572 25.54 25.297 25.21 25.106 08HA020 2 8 1992 14 25.56 25.539 25.369 25.294 25.203 25.102 08HA020 2 8 1992 15 25.557 25.53 25.358 25.291 25.196 25.095 08HA020 2 8 1992 16 25.571 25.526 25.355 25.288 25.193 25.095 08HA020 2 8 1992 17 25.574 25.519 25.352 25.287 25.19 25.092 08HA020 2 8 1992 18 25.574 25.51 25.348 25.278 25.184 25.089 08HA020 2 8 1992 19 25.571 25.5 25.348 25.275 25.177 25.085 08HA020 2 8 1992 20 25.561 25.493 25.348 25.271 25.173 25.084 08HA020 2 8 1992 21 25.557 25.486 25.339 25.307 25.17 25.081 08HA020 2 8 1992 22 25.554 25.48 25.338 25.304 25.167 25.081 08HA020 2 8 1992 23 25.551 25.473 25.332 25.304 25.157 25.098 08HA020 2 8 1992 24 25.544 25.466 25.325 25.298 25.156 25.101 08HA020 2 8 1992 25 25.541 25.459 25.315 25.292 25.152 25.091

Water Survey of Canada Station 08HA029 7 Quamichan Lake Water levels - Datum adjusted to ASL Station Discontinued

ID PARAM TYPE Year DD Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 08HA020 2 8 1992 26 25.557 25.449 25.309 25.285 25.146 25.085 08HA020 2 8 1992 27 25.56 25.443 25.309 25.281 25.142 25.085 08HA020 2 8 1992 28 25.554 25.449 25.308 25.276 25.139 25.085 08HA020 2 8 1992 29 25.604 25.44 25.312 25.27 25.135 25.083 08HA020 2 8 1992 30 25.604 25.436 25.309 25.255 25.135 25.083 08HA020 2 8 1992 31 25.43 25.25 25.132 08HA020 2 8 1993 1 25.809 25.694 25.607 25.454 25.365 25.239 08HA020 2 8 1993 2 25.796 25.694 25.603 25.448 25.354 25.236 08HA020 2 8 1993 3 25.793 25.693 25.6 25.445 25.352 25.229 08HA020 2 8 1993 4 25.783 25.687 25.594 25.451 25.346 25.226 08HA020 2 8 1993 5 25.776 25.693 25.587 25.438 25.342 25.225 08HA020 2 8 1993 6 25.766 25.694 25.574 25.434 25.339 25.222 08HA020 2 8 1993 7 25.752 25.7 25.57 25.431 25.332 25.222 08HA020 2 8 1993 8 25.766 25.697 25.564 25.425 25.319 25.222 08HA020 2 8 1993 9 25.769 25.699 25.57 25.415 25.329 25.216 08HA020 2 8 1993 10 25.769 25.7 25.564 25.411 25.329 25.209 08HA020 2 8 1993 11 25.763 25.704 25.554 25.407 25.326 25.209 08HA020 2 8 1993 12 25.763 25.703 25.553 25.405 25.322 25.208 08HA020 2 8 1993 13 25.752 25.696 25.55 25.404 25.315 25.206 25.151 08HA020 2 8 1993 14 25.749 25.687 25.547 25.411 25.312 25.196 08HA020 2 8 1993 15 25.749 25.683 25.544 25.405 25.309 25.195 08HA020 2 8 1993 16 25.742 25.683 25.54 25.405 25.306 25.192 08HA020 2 8 1993 17 25.746 25.67 25.534 25.401 25.299 25.192 08HA020 2 8 1993 18 25.733 25.664 25.528 25.398 25.296 25.191 08HA020 2 8 1993 19 25.732 25.654 25.525 25.394 25.292 25.189 08HA020 2 8 1993 20 25.719 25.653 25.525 25.391 25.286 25.188 08HA020 2 8 1993 21 25.719 25.644 25.524 25.391 25.285 25.187 08HA020 2 8 1993 22 25.719 25.644 25.495 25.385 25.282 25.187 08HA020 2 8 1993 23 25.713 25.644 25.488 25.378 25.282 25.186 08HA020 2 8 1993 24 25.703 25.643 25.491 25.272 25.177 08HA020 2 8 1993 25 25.709 25.624 25.488 25.374 25.282 25.177 08HA020 2 8 1993 26 25.706 25.623 25.475 25.371 25.282 25.177 08HA020 2 8 1993 27 25.703 25.604 25.471 25.368 25.274 25.177 08HA020 2 8 1993 28 25.702 25.604 25.468 25.371 25.265 25.176 08HA020 2 8 1993 29 25.703 25.604 25.465 25.255 25.167 08HA020 2 8 1993 30 25.703 25.603 25.451 25.374 25.242 25.167 08HA020 2 8 1993 31 25.61 25.371 25.239

Water Survey of Canada Station 08HA029 8 Quamichan Lake Outlet Control

Table 2

Duncan Bay Climate Data: Environment Canada Canadian Climate Normals 1971-2000

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Canadian Climate Normals 1971-2000 http://climate.weatheroffice.ec.gc.ca/climate_normals/results_e.html?...

[français] [Back]

Canadian Climate Normals 1971-2000

The minimum number of years used to calculate these Normals is indicated by a code for each element. A "+" beside an extreme date indicates that this date is the first occurrence of the extreme value. Values and dates in bold indicate all-time extremes for the location.

NOTE!! Data used in the calculation of these Normals may be subject to further quality assurance checks. This may result in minor changes to some values presented here.

DUNCAN FORESTRY BRITISH COLUMBIA

Latitude: 48° 46.200' N Longitude: 123° 40.800' W Elevation: 06.00 m Climate ID: 1012570 WMO ID: TC ID:

Temperature: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year Daily Average (°C) 2.6 4.1 5.9 8.5 11.9 14.7 17 17.1 13.8 9.3 5 2.9 9.4 Standard Deviation 1.7 1.6 1.2 1.1 0.9 1.1 1 1.1 1.1 1.1 1.7 1.9 0.5 Daily Maximum (°C) 6.1 8 10.6 13.9 17.4 20.3 23.3 23.6 20.3 14.8 8.8 6.3 14.5 Daily Minimum (°C) -1.1 0.1 1.2 3 6.2 9.1 10.7 10.5 7.2 3.8 1.2 -0.5 4.3 Extreme Maximum (°C) 15 19.4 21.1 25.6 33.5 33 37.2 36.5 34.5 28.5 18.9 17 Date (yyyy/dd) 1961/14+ 1968/27 1965/10 1971/25 1983/28 1982/18 1958/27 1981/08 1988/02 1987/01 1975/03 1980/25 Extreme Minimum (°C) -21.1 -15.5 -12 -3.9 -2.2 1.7 3.3 2.2 -3 -6.7 -17 -21.7 Date (yyyy/dd) 1969/25 1989/04 1989/03 1964/18+ 1965/05+ 1976/03 1971/02 1973/18 1983/29 1961/21 1985/23 1968/30 Precipitation: Rainfall (mm) 129.5 122.2 99.7 53.9 44.4 37.3 20.3 25.3 46.7 79.5 163.3 171.1 993.1 Snowfall (cm) 15.8 7.9 2 0.2 0 0 0 0 0 0.4 5.4 14.4 46.1 Precipitation (mm) 145.3 130.1 101.7 54 44.4 37.3 20.3 25.3 46.7 80 168.8 185.5 1039.2 Extreme Daily Rainfall (mm) 73.9 46 42 45 28 26.6 23.9 49.8 37.6 54.6 59.8 72 Date (yyyy/dd) 1960/28 1983/19 1987/02 1970/08 1984/25 1980/07 1974/16 1975/22 1972/20 1975/16 1983/14 1979/16 Extreme Daily Snowfall (cm) 32.3 30 21.8 2 0 0 0 0 0 8 27 33 Date (yyyy/dd) 1965/23 1989/17 1961/05 1981/11 1959/01+ 1959/01+ 1958/01+ 1958/01+ 1958/01+ 1984/31 1985/26 1968/30 Extreme Daily Precipitation (mm) 73.9 46 42 45 28 26.6 23.9 49.8 37.6 54.6 59.8 72 Date (yyyy/dd) 1960/28 1983/19 1987/02 1970/08 1984/25 1980/07 1974/16 1975/22 1972/20 1975/16 1983/14 1979/16 Extreme Snow Depth (cm) 39 5 18 0 0 0 0 0 0 0 54 39 Date (yyyy/dd) 1985/01+ 1989/17 1989/02 1981/01+ 1981/01+ 1981/01+ 1981/01+ 1980/01+ 1981/01+ 1981/01+ 1985/27+ 1984/30+ Days with Maximum Temperature: <= 0 °C 1.6 0.26 0.05 0 0 0 0 0 0 0 0.5 1.4 3.9 > 0 °C 29.4 28 31 30 31 30 31 31 30 31 29.5 29.6 361.4 > 10 °C 3.2 6.6 16.5 25.6 30.5 30 31 31 29.9 28.6 9.2 3.5 245.6 > 20 °C 0 0 0 2.2 6.6 13.8 23.6 24.4 13.6 2.1 0 0 86.3 > 30 °C 0 0 0 0 0.17 0.67 1.5 2 0.39 0 0 0 4.8 > 35 °C 0 0 0 0 0 0 0 0.11 0 0 0 0 0.11 Days with Minimum Temperature: > 0 °C 11.6 14.6 17.5 23.1 30.7 30 31 31 29.2 23.4 17.9 14.1 274 <= 2 °C 24.3 19.8 19.4 12.8 2.4 0.06 0 0 1.5 11.8 17.9 22.2 132 <= 0 °C 19.4 13.7 13.5 6.9 0.33 0 0 0 0.79 7.6 12.1 16.9 91.3 < -2 °C 10.3 6.8 4.5 0.68 0 0 0 0 0.11 1.4 6.2 10.2 40.2 < -10 °C 1.4 0.61 0.05 0 0 0 0 0 0 0 0.41 0.53 3 < -20 °C 0 0 0 0 0 0 0 0 0 0 0 0 0 < - 30 °C 0 0 0 0 0 0 0 0 0 0 0 0 0 Days with Rainfall: >= 0.2 mm 14.9 15.5 15 11.7 10.8 8.5 5.4 5.8 8.6 12.1 17.2 16 141.5 >= 5 mm 7.9 7.3 6.8 4 3.2 2.8 1.3 1.7 2.9 4.9 9.9 8.8 61.5 >= 10 mm 4.5 4.6 3.3 1.5 1 1.1 0.47 0.58 1.3 2.4 5.9 5.6 32.2 >= 25 mm 0.88 0.83 0.37 0.11 0.05 0.06 0 0.11 0.22 0.5 1.6 1.8 6.5 Days With Snowfall: 1 of 1 >= 0.2 cm 3.1 1.9 0.63 0.11 0 0 0 0 0 0.06 1.1 2.98/6/20079.8 1:17 PM Quamichan Lake Outlet Control

Table 3

Gaylord Stewart Stage Data: “Quamichan Lake Water Levels” Summary 1988-2007

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Water Levels ref: Gaylord Stewart

The following data set was kindly provided by Mr. Gaylord Stewart. The data was collected by the Stewart family at a private stage plate installed in the lake adjacent to their property at 6387 Lakes Road. The stage plate is in feet, and the datum was referenced to ASL by transfer from a benchmark in Duncan. The data set was converted to metric, and adjusted by 51 mm to correspond to the project Reference Mark. Adjustment was required due to the difference in the original benchmark elevations. Data set transcribed from paper copy 30 July, 2007. DATE LEVEL (feet) LEVEL (m) Adjusted LEVEL (m) 1-Sep-88 82.85 25.25 25.20 29-Dec-94 85.94 26.19 26.14 15-Jan-95 85.67 26.11 26.06 1-Oct-93 82.63 25.19 25.13 Oct-94 82.20 25.05 25.00 Oct-95 82.48 25.14 25.09 Oct-96 82.65 25.19 25.14 1-Nov-96 83.33 25.40 25.35 1-Dec-96 85.15 25.95 25.90 14-Dec-96 86.08 26.24 26.19 1-Jan-97 86.68 26.42 26.37 2-Jan-97 87.01 26.52 26.47 3-Jan-97 87.09 26.55 26.49 4-Jan-97 87.08 26.54 26.49 17-May-97 84.8 25.85 25.80 4-Sep-98 82.5 25.15 25.10 29-Jan-99 86.91 26.49 26.44 2-Mar-00 84.8 25.85 25.80 2-May-00 84.00 25.60 25.55 20-Oct-00 82.3 25.09 25.03 14-Jun-01 83.7 25.51 25.46 3-Jul-01 83.4 25.42 25.37 13-Jun-02 83.7 25.51 25.46 6-Jul-02 83.5 25.45 25.40 1-Apr-03 85.6 26.09 26.04 22-Apr-03 85.2 25.97 25.92 3-Sep-03 82.7 25.21 25.16 18-Jan-04 86.00 26.21 26.16 24-Apr-04 84.6 25.79 25.74 2-May-05 85.1 25.94 25.89 18-May-05 84.9 25.88 25.83 1-Jul-05 84.5 25.76 25.70 8-Jul-05 84.3 25.69 25.64 17-Jul-05 84.2 25.66 25.61 8-Aug-05 83.75 25.53 25.48 5-Sep-05 83.4 25.42 25.37 25-Sep-05 83.3 25.39 25.34 11-Nov-05 83.8 25.54 25.49 11-Dec-05 84.1 25.63 25.58 24-Dec-05 84.7 25.82 25.77 7-Jan-06 86.2 26.27 26.22 14-Jan-06 87.00 26.52 26.47 9-Mar-06 86.8 26.46 26.41 4-Apr-06 85.3 26.00 25.95 15-Apr-06 84.9 25.88 25.83 25-Apr-06 84.7 25.82 25.77 21-May-06 84.3 25.69 25.64 6-Jun-06 84.3 25.69 25.64 1-Jul-06 84.0 25.60 25.55 30-Jul-06 83.5 25.45 25.40 16-Aug-06 83.3 25.39 25.34 19-Sep-06 82.8 25.24 25.19 1-Oct-06 82.8 25.24 25.19 5-Nov-06 82.1 25.02 24.97 1-Nov-06 82.8 25.24 25.19 12-Nov-06 83.7 25.51 25.46 19-Nov-06 85.1 25.94 25.89 4-Dec-06 85.7 26.12 26.07 11-Dec-06 85.9 26.18 26.13 15-Dec-06 86.6 26.40 26.34 21-Dec-06 86.7 26.43 26.38 1-Jan-07 86.6 26.40 26.34 8-Jan-07 87.0 26.52 26.47 14-Mar-07 85.7 26.12 26.07 13-Apr-07 84.8 25.85 25.80 6-Aug-07 84.17 25.66 25.60

Max. = 26.49 Min.= 24.97 Range= 1.52

8-08-07 D.G.V. Engineering Services Ltd. Lake Levels G Stewart.xls Nanaimo, BC 1 Quamichan Lake Outlet Control

Table 4

Water Licence Table: “Water Licences Report” Quamichan Lake – current and pending

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Water Licences Report http://www.elp.gov.bc.ca:8000/pls/wtrwhse/water_licences.output?...

Water Licences Report

Scroll to bottom of page for unique count of licences and/or applications found in your search

WR Map/ Licence Stream Qty Rediv Water Licence Priority Issue Point Purpose Quantity Units Licensee Process Status No Name Flag Flag District/Precinct Status Date Date Code DAVIS JOHN E 1884 MARTIN 8708D U4 Quamichan Sec. 18 C025384 Domestic 1000 GD T N PLACE RR 1 VIC - DUNCAN Current 19590915 0 (PD32129) Lake Amendment DUNCAN BC V9L1M3 MORGAN ROGER L & 8708D D5 Quamichan PIERRETTE M C028861 Domestic 500 GD T N VIC - DUNCAN Current N/A 19631219 0 (PD32130) Lake 1880 MARTIN PL DUNCAN BC V9L5W1 ROBIN EDWIN P 8708D-1 Quamichan 6358 C035827 L5 Domestic 500 GD T N VIC - DUNCAN Current N/A 19700224 0 Lake LANSDOWNE (PD32133) PL DUNCAN BC V9L5R2 DICKEY ROBERT N & 8708D-1 JUDITH A Quamichan C036627 M5 Irrigation 12 AF T N 54 EAST VIC - DUNCAN Current N/A 19700721 0 Lake (PD32141) LONGDEN AVE ARCADIA CA 91006 USA BEAVERIDGE 8708D-1 KATHLEEN M Quamichan C043295 S5 Domestic 500 GD T N 6184 ROOME VIC - DUNCAN Current N/A 19730405 0 Lake (PD32142) RD DUNCAN BC V9L4N8 WHITTOME JAMES L 8708D-1 Quamichan 201-58 C047107 Y3 Irrigation 6 AF T N VIC - DUNCAN Current N/A 19760402 0 Lake STATION ST (PD32121) DUNCAN BC V9L1M4 MORRIS PETER M & 8708D D6 Quamichan WENDY M C049356 Irrigation 2.2 AF T N VIC - DUNCAN Current N/A 19510807 0 (PD32127) Lake 6501 LAKES RD DUNCAN BC V9L5V7 MILLAR CATHERINE D 8708D F6 Quamichan C052655 Irrigation 6 AF T N 1774 STAMPS VIC - DUNCAN Current N/A 19780407 0 (PD32139) Lake RD DUNCAN BC V9L5W2 COSH LOIS O & JAMES C 8708D E6 Quamichan C052656 Irrigation 5 AF T N PO BOX 491 VIC - DUNCAN Current N/A 19771230 0 (PD32137) Lake DUNCAN BC V9L3X8 VAN JAARSVELD CORNELIUS M 8708D J3 Quamichan AND TERESA C052804 Irrigation 9 AF T N VIC - DUNCAN Current N/A 19770921 0 (PD32128) Lake W 6583 LAKES RD DUNCAN BC V9L5V9

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LENKO PAMELA M D 8708D H6 Quamichan C054481 Irrigation 10 AF T N 1708 STAMPS VIC - DUNCAN Current N/A 19790723 0 (PD32149) Lake ROAD DUNCAN BC V9L5W2 LENKO PAMELA M D 8708D H6 Quamichan C054482 Irrigation 10 AF T N 1708 STAMPS VIC - DUNCAN Current N/A 19790723 0 (PD32149) Lake ROAD DUNCAN BC V9L5W2 HUNT RICHARD & 8708D V5 Quamichan SYLVIA C057295 Irrigation 3 AF T N VIC - DUNCAN Current N/A 19721212 0 (PD32131) Lake 1844 STAMPS RD DUNCAN BC V9L5W1 SADD TOM E & ARDITH A 8708C F5 Quamichan C063543 Irrigation .33 AF T N 6307 LAKES RD VIC - DUNCAN Current N/A 19790924 0 (PD32124) Lake RR 1 DUNCAN BC V9L1M3 NEWCOMB D ELIZABETH 8708D-1 Quamichan 1759 MAPLE C063714 L4 Stockwatering 500 GD T N VIC - DUNCAN Current N/A 19560830 0 Lake BAY RD (PD32115) DUNCAN BC V9L4T6 HEPTING LORRAINE A 8708D G3 Quamichan C065886 Irrigation 6.25 AF T N 1808 STAMPS VIC - DUNCAN Current N/A 19820730 0 (PD32136) Lake RD DUNCAN BC V9L5W2 TO BE DETERMINED PLEASE CONTACT 8708D-1 Quamichan NEAREST Apportionment C068006 T3 Irrigation 30 AF T N VIC - DUNCAN Pending 19530803 0 Lake MINISTRY OF Pend (PD32152) ENVIRONMENT WATER MANAGEMENT OFFICE WOOD TINA J 6159 LAKES RD 8708C CC Quamichan C072679 Irrigation 8 AF T N NORTH VIC - DUNCAN Current N/A 19491221 0 (PD32116) Lake COWICHAN BC V9L4J6 LAMBRECHT HELGA 8708D-1 Quamichan Res. 1763 MAPLE C108340 D4 .25 AF T N VIC - DUNCAN Current N/A 19540625 19950120 Lake Lawn/Garden BAY RD (PD32112) DUNCAN BC V9L5N6 WALBOHM HANS F 8708D-1 Quamichan Res. 1765 MAPLE C108341 D4 .25 AF T N VIC - DUNCAN Current N/A 19540625 19940120 Lake Lawn/Garden BAY RD (PD32112) DUNCAN BC V9L5N6 JIREH FARMS LTD C/O VAN BOVEN M & J 8707A T3 Quamichan C117271 Irrigation 20 AF T N 2135 VIC - DUNCAN Current N/A 19690826 20020415 (PD32018) Lake QUAMICHAN PARK RD DUNCAN BC V9L3B5

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HALVORSON 8708D-1 JAMES P Quamichan C117754 N3 Stockwatering 250 GD T N 1246 BAZETT VIC - DUNCAN Current N/A 19530502 20021120 Lake (PD32153) RD DUNCAN BC V9L5S8 MILLAR CATHERINE D 8708D C3 Quamichan F013998 Domestic 500 GD T N 1774 STAMPS VIC - DUNCAN Current N/A 19491126 0 (PD32138) Lake RD DUNCAN BC V9L5W2 CHUDLEIGH JANETTE 8708C BB Quamichan PO BOX 138 F013999 Domestic 500 GD T N VIC - DUNCAN Current N/A 19491212 0 (PD32119) Lake STN MAIN DUNCAN, BC V9L3X1 PRICE KEITH F T 2151 8707A F3 Quamichan F014000 Domestic 500 GD T N QUAMICHAN VIC - DUNCAN Current N/A 19491215 0 (PD32019) Lake PARK RD DUNCAN BC V9L5E9 BOGGS HERBERT W DR 8707A E3 Quamichan Sec. 18 F014137 Domestic 1000 GD T N 5995 VIC - DUNCAN Current 19491126 0 (PD32025) Lake Amendment ROTHWELL RD DUNCAN B C V9L3B6 HAYES JOHN S 1931 MAPLE 8707B G3 Quamichan F015067 Domestic 1000 GD M N BAY RD RR 5 VIC - DUNCAN Current N/A 19491121 0 (PD32022) Lake DUNCAN BC V9L5M4 HAYES JOHN S 1931 MAPLE 8707B W Quamichan " Domestic 1000 GD M N BAY RD RR 5 VIC - DUNCAN Current N/A 19491121 0 (PD32023) Lake DUNCAN BC V9L5M4 DREW CAMERON R & MAEVE B 8707A F3 Quamichan F015111 Domestic 1000 GD M N 6628 VIC - DUNCAN Current N/A 19500307 0 (PD32019) Lake HENDERSON RD DUNCAN BC V9L5W2 DREW CAMERON R & MAEVE B 8708D F3 Quamichan " Domestic 1000 GD M N 6628 VIC - DUNCAN Current N/A 19500307 0 (PD32140) Lake HENDERSON RD DUNCAN BC V9L5W2 PHILIPPSON DANIEL 8707B E3 Quamichan C/O 103-149 Sec. 18 F016181 Domestic 1000 GD T N VIC - DUNCAN Current 19521208 0 (PD32024) Lake INGRAM ST Amendment DUNCAN BC V9L1N8 LEROY RONALD E & 8708D-1 CYNTHIA R D Quamichan F016630 R3 Domestic 1000 GD T N 1785 MAPLE VIC - DUNCAN Current N/A 19521202 0 Lake (PD32106) BAY RD DUNCAN BC V9L5N6 LEROY Quamichan RONALD E & " " Irrigation 2 AF T N VIC - DUNCAN Current N/A 19521202 0 Lake CYNTHIA R D 1785 MAPLE

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BAY RD DUNCAN BC V9L5N6 WOODS MURRAY C & 8708D A4 Quamichan CORNELIA M F016632 Domestic 1000 GD T N VIC - DUNCAN Current N/A 19540601 0 (PD32134) Lake 1834 STAMPS RD DUNCAN BC V9L5W1 JOSSY ERIN 8708D-1 1773 MAPLE Quamichan F017044 N4 Domestic 1000 GD T N BAY RD VIC - DUNCAN Current N/A 19570516 0 Lake (PD32114) DUNCAN BC V9L4T5 GRIMES RICHARD & 8708D-1 BARBARA M Quamichan F017082 S3 Domestic 1000 GD T N 1781 MAPLE VIC - DUNCAN Current N/A 19540215 0 Lake (PD32111) BAY ROAD RR 5 DUNCAN BC V9L5N6 GRIMES RICHARD & BARBARA M Quamichan " " Irrigation 4.3 AF T N 1781 MAPLE VIC - DUNCAN Current N/A 19540215 0 Lake BAY ROAD RR 5 DUNCAN BC V9L5N6 TREBELL FRANCIS M 8708D-1 Quamichan 1733 MAPLE F017111 E4 Domestic 500 GD T N VIC - DUNCAN Current N/A 19540903 0 Lake BAY RD (PD32118) DUNCAN BC V9L5N6 HOWROYD JOHN 8708D Quamichan 4308 F017162 W3 Domestic 1000 GD T N VIC - DUNCAN Current N/A 19540225 0 Lake HOULIHAN PL (PD32145) VICTORIA BC V8N3T1 STEWART ALAN GAYLARD 8708C B3 Quamichan MACDONALD Transfer/Appurt F017513 Irrigation 32 AF T N VIC - DUNCAN Current 19540111 0 (PD32125) Lake AMBLECOTE Pend 6325 LAKES ROAD DUNCAN BC V9L5V6 WATERS BARRY A & 8708C N3 Quamichan CATHY MAE Sec. 18 F017748 Domestic 500 GD T N VIC - DUNCAN Current 19560515 0 (PD32120) Lake 6247 LAKES RD Amendment DUNCAN BC V9L4J8 ROBERTSON MARGARET L 8708D-1 6212 Quamichan F019608 K5 Domestic 500 GD T N CHURCHILL VIC - DUNCAN Current N/A 19660401 0 Lake (PD32161) RD RR 5 DUNCAN BC V9L4T6 TAYLOR DONALD E & DARLENE G 8708D-1 Quamichan 6240 F019609 R4 Domestic 850 GD T N VIC - DUNCAN Current N/A 19470808 0 Lake CHURCHILL (PD32122) ROAD RR 5 DUNCAN B C V9L4T6

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RIDENOUR KEN D 8708D-1 Quamichan 1683 MAPLE Sec. 18 F019685 X4 Domestic 830 GD T N VIC - DUNCAN Current 19470808 0 Lake BAY ROAD RR Amendment (PD32159) 5 DUNCAN B C V9L5N7 VAN JAARSVELD CORNELIUS M 8708D J3 Quamichan AND TERESA F049559 Irrigation 57.8 AF T N VIC - DUNCAN Current N/A 19510807 0 (PD32128) Lake W 6583 LAKES RD DUNCAN BC V9L5V9

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5 of 5 8/7/2007 10:11 AM Quamichan Lake Outlet Control

Appendix C

Survey Detail

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Quamichan Lake Outlet Control

Survey Detail:

The land survey of both the lake outlet and the upper reach of Quamichan Creek were undertaken in July 2007. The survey consisted of several components: • The channel survey using total station instrument and tied to legal property corner iron pins. This process defined the creek, provided cross section data of the channel and horizontal control relative to legal boundaries. • Placement of the "New Reference Mark" on the concrete wall at Art Mann Park. Details of the placement are shown on the survey drawing. The reference mark is a steel anchor bolt set in the vertical face of the shoreline retaining wall, and is described in detail below. The vertical control for the survey and for the New Reference Mark is tied to an existing control monument. The survey was completed with vertical control closure to less than 2 mm. • General location definition and lake bathymetry was completed using hand held GPS to confirm existing mapping obtained from a variety of sources. The GPS data correlated well with cadastral mapping of the park area and the lake shoreline to approximately 1 m precision that is more than adequate for the purpose of the study. Lake bottom data at the lake outlet were obtained by direct measurement and portable depth sounder. • Local surficial materials were noted during the site investigation and survey. As appropriate, materials are noted on the survey.

The channel survey consists of three sections. The first section is the channel from the lake to the small footbridge that identifies the start of Quamichan Creek. This section was assessed from the water using hand held GPS and a probe to locate the surface of the lake bottom and to penetrate the material to the firm substrate. The second section extends from the footbridge to about 140 m downstream near the old stream gauge site. This section was surveyed with a total station, and detailed sections were obtained. The third section of channel south and downstream of that point is not accessible to survey because of thick vegetation. Observation of the fact that the water was not backed up, and the excavated channel where observed is consistent with the surveyed reach suggested more detailed survey was not required. The drawing of the lake outlet and the initial reach of Quamichan Creek with notes attached as Appendix A, Figure 4, Sheets 1 and 2. The system profile information is shown as Appendix A, Figure 4, Sheet 3.

The creek channel has an average base width of about 4 m, with banks sloping at 1:1 or steeper in many areas. The base slope of the channel is low; the average slope is approximately 0.1%. There is no clear hydraulic control section. A beaver dam as shown on the drawing obstructs the channel, and there is some, generally small, woody debris in the channel adding to the channel roughness. Such debris has significant aquatic habitat value.

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Bedrock is at or near the surface around the lake outlet. The bedrock is sedimentary sandstone, of which at least the surface material that was apparently easily ripped during the excavation of the reach of Quamichan Creek channel. The creek channel bottom generally appears to consist of a shallow layer of organic muck, gravel and fragments over bedrock with some areas of silty sand and gravel (glacial Till) especially noted on the west side of the channel. The channel at the lake outlet, through the aquatic vegetation to the footbridge, has a deep layer of organic muck over what is assumed to be bedrock. Bedrock is exposed at the lakeshore in the general area. Bedrock is exposed at Art Mann Park. The materials encountered suggest that foundations for the structure will not present a problem. The consistent presence of bedrock suggest that any contemplated deepening of the Quamichan Creek channel will be costly since any such efforts will involve a relatively large area with associated significant environmental impacts.

The profile of the Quamichan Creek Channel consists of the apparently dredged lake outlet route through the aquatic vegetation to the high point in the bedrock near the small footbridge near Art Mann Park. The highest point in the "organic muck" was 24.90 m. The top of the bedrock surface in the approach channel reaches 24.89 m. at the lily pad in the channel immediately upstream of the footbridge. The approximately 140 m reach of the creek from the footbridge to the property line near the creek stream gauge was surveyed and cross sections were developed. The bottom of the excavated channel is flat on bedrock with an average elevation of 24.9 m. The "effective" channel bottom, considering debris etc., is estimated at 25.0 m. Survey south beyond that property line is not practical because the channel and riparian areas are choked in blackberries, but the excavated channel continues at least another 150 m before the break in slope where the creek flows down over the bedrock surface for several meters. Since water level is not backed up in this reach at the gauging station, it is clear that the effective channel bottom does not exceed that of the upstream reach, and is therefore approximately 24.9 m. Since no observable "steps" in the observed pools of water were noted, it is suggested with a high degree of confidence that there is little or no channel slope in this reach of excavated channel.

The hydraulic control in Quamichan Creek that controls the lake level is variable depending on conditions. The slope of the creek channel is flat. During low flow conditions, the lake level is governed by channel debris and obstructions such as the beaver dam in the reach from the lake outlet to the WSC site. At moderate high flows, the hydraulic control is a combination of debris and simple channel capacity of the outlet reach to the WSC station. At peak flows, the break in channel slope about 300 m downstream or the channel roughness to that point could control the lake discharge. However, any large obstruction or significant debris could in fact move the control anywhere in the section from the footbridge to the downstream break in slope.

Currently, the beaver dam is the lake level control under all conditions.

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Appendix D

Channel Capacity:

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Channel Capacity:

The existing discharge from the lake is controlled by the channel capacity of Quamichan Creek. The original creek channel appears to have been a more sinuous creek that was 0.5 to 1.0 m. higher than the existing channel that is clearly an excavated channel. The existing channel is relatively straight with steep sides and in many areas was constructed working upstream. Spoil from the excavation is mounded on either side of the channel that appears to have more or less followed the course of the old creek. It is therefore not possible to clearly state where the original control point in the channel was, or to state what the original channel width was. It is likely that the original channel was a lower gradient, wide channel. Both the new and evidence of the original Quamichan Creek channels are shown on Section A on the drawing. It is understood that the new channel was constructed before the 1970's by agricultural interests to provide earlier access to low-lying areas. The actual date of the work is unknown.

The width of the new channel is quite consistent for at least 130 m, and in many areas the base of the channel is clearly on bedrock. There does not appear to be any easily modified control section with an attendant hydraulic drop, and therefore any attempt to increase discharge capacity of the lake requires either lowering or widening a significant section of channel with attendant impacts. It is therefore concluded that any proposed control structure should operate with the existing channel geometry.

Channel capacity is controlled by several factors including the channel geometry, the "roughness factor" that integrates the channel surface roughness and the presence of debris, and in this case the nature of the hydraulic control. The channel capacity is best described as the relationship between the flow depth and the flow rate, and can be derived from empirical relationships and estimates of the roughness factor, or the curve can be developed for the site by a series of flow measurements over time.

The latter was done indirectly by WSC for their station on Quamichan Creek. The following figure provides the relationship.

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

Quamichan Creek WSC Station 08HA021

3.000

2.500

2.000

1.500

1.000 Discharge (cms)

0.500

0.000 24.80 25.00 25.20 25.40 25.60 25.80 26.00 26.20 26.40 Water Level (m - ASL)

The figure is based on flow measurements, and the curve has been extrapolated above bank full level for convenience. At bank full, the water level would be approximately 26.0 m ASL and this suggests that the bank full flow is approximately 1.85 cms,

Using this flow rate and depth at the WSC station and assuming an average channel section and estimating the channel roughness coefficient, the lake level was estimated at approximately 26.6 m ASL. This is reasonably consistent with anecdotal information of highest water levels observed in Quamichan Creek, and the highest lake levels observed in the Stewart data (Table 3, appendix B) as 26.49 m.

It is therefore concluded that the maximum channel capacity is in the order of 1.85 to perhaps 2.0 cms.

The proposed structure, with the gates fully open, is intended to allow full channel flow.

If channel capacity increases are required, this could be achieved, in order of increased local impacts by:

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC

Quamichan Lake Outlet Control

o Hand removal of some larger debris, removal of the beaver dam etc. will ensure the channel capacity is maximized without compromising the local environment or aesthetic values. This would ensure field access similar to recent memory. o Intensive hand clearing involving the removal of all woody debris and annual maintenance could improve maximum channel capacity about 10%. This would have a relatively small impact (certainly less than a week) relative to earlier access to fields in the spring. o Deepening the channel - likely not practical since it involves rock excavation over the length of the excavated channel (over 200 m) and into the lake. The rock in the base of the existing channel appears to be sound, and likely limited the depth of excavation when the channel was established before about 1970. Heavier machinery now available can rip the base rock, but the effort and cost is likely significant. Clearly, the deeper the channel, the lower the lake level that can be achieved. o Widening the channel - this would involve rock excavation but the rock involved is weathered and was excavated relatively easily in the earlier construction. Channel widening would improve maximum channel capacity, but it is noted that the gains diminish rapidly as the water level lowers. Widening would be most effective for reducing mid winter peak lake levels rather than improving spring access to fields

It is suggested that the return to recent historical conditions can be achieved with hand removal of large debris and the removal of obstructions.

4-Feb-08 D.G.V. Engineering Services Ltd. 9073-1 Outlet Control Report Final lp.doc Nanaimo, BC