The following are two complete reports on the EACT watershed by Allen Isaacson.
HYDROLOGY REPORT for SAWAN/ANDERSON WATERSHEDby Allen Isaacson, Professional Hydrologist INTRODUCTION /GENERAL DESCRIPTION OF LANDSCAPE / FISH POND AND WATER COURSE / WATER SUPPLY DRAINAGES / CONCLUSION
HYDROLOGY REPORT FOR ANDERSON, ELLIOTT, CHRISTIAN, AND TROZZOby Allen Isaacson, Professional Hydrologist
HYDROLOGY REPORT for SAWAN/ANDERSON WATERSHED by Allen Isaacson, Professional Hydrologist On June 16, 1997, 1 accompanied local Sawan I Anderson watershed residents, Stephan Martineau and Jim Merkel on a field trip tour of the proposed road construction and timber harvest activities by Slocan Forest Products in the Sawan I Anderson watershed. This area includes the following creeks: Sawan, Anderson, Goloff Chou, Pete's pond, and many more unnamed seeps and springs. The areas we observed in detail were;
This report points out the poor location and the potential problems that could arise from the proposed road construction and timber activities. It shows the magnitude of impact on the small, extremely fragile watersheds, which will cause damage to the watercourses and the water supplies for many individual water users.
GENERAL DESCRIPTION OF LANDSCAPE The following is a general description of the topography for the area across the landscape where the road constriction and timber harvest proposal are located. This analysis looks specifically at the road location just off of Rooster Road and above property ft 8947. The intent of the field trip tour was not to look at the entire planned area, but just to focus on the first proposed activities and to go into depth hydrologically in these areas.
We began our tour at the lower end of the watershed, meeting with Pete Ferguson, the landowner whose land was expropriated on March 4 1997 in order to provide an access Forest Service road through his property. The proposed access road runs through at least three channels that are well defined in the field and that were running water at the time of our field trip tour. These channels, together with the wetland seeps and overland flow, make up the water source for a pond, located on his property. Historically the pond had fish and was used by local residents as a fishing source (according to local information). Mr. Ferguson has established a population of rainbow trout (Salmo gairdneri) for commercial use. The pond depends on the flow of water for bringing in nutrients, aquatic insects, terrestrial insects and oxygenated water. This is especially important in the late summer and during ice and snow cover in the. winter months. Without an outside source it is very probable that this pond would be deprived of oxygen during these months. There seems to be some controversy about the historical prospective and origin of the watercourse and flow that supply this pond At this point in time, however, it should not matter whether the origin is man-made or natural. A wetland has been established with standing water and the pond. Water has been flowing to this site for at least several decades, giving the area enough time to evolve into a water dependent community of flora and fauna. The native vegetation has changed and now represents the wetland species. The pond has an outlet, and a culvert has been put in Rooster road at a depth of about 10-12 inches above the ditch ground so as to hold more water in the wetland, which drains in the spring towards the highway. There must have been a historical watercourse here, as the highway construction also found it important to locate a culvert where the water flows. Pete Ferguson has applied for Commercial Water Rights and has had a Private Fish Culture Permit since 1994. The first section of the proposed road is located on the expropriated right of way, about 15 meters from the pond. Should the planned road construction proceed, the watercourses supplying the pond, as well as wetland values and areas of standing water, would be covered over. These areas, together with the subsurface flows through this site, are important for the survival of the pond and the trout crop. Especially the first 150-200. meters of the proposed road (off of Rooster Road) are in a very poor location. I recommend against the construction of the road as it is currently planned for several reasons:
We continued the tour to the area above property ft 8947 where a cut block and the road are proposed. This area lies above several creeks: Anderson, Sawan, Goloff and Chou. It is very interesting to view the beginning seeps and wet areas that come together to form these creeks which provide people down stream with a year round water supply. These areas are very fragile and have evolved over many years of natural conditions. Due to the glaciation history of the valley the watercourses and slope hydrology are very close to the surface. Layers of compacted till and other geological structures along with bedrock control the movement of water near the surfaces. The proposed road is located where most of the subsurface water flowing by gravity down the slopes is beginning to surface or is flowing very close to the surface. The subsurface flow can easily be intercepted by any activity that digs into the surface soil - either from dragging logs where the soil is gouged or from road or skidder construction. In such wet landforms I have observed examples where surface water is initiated though accidental impacts, even when care is being exercised. IT CAN NOT BE EMPHASIZED ENOUGH, THAT THESE SEEP, SPRING AND SMALL WATERCOURSES ARE EXTREMELY FRAGILE TO ANY IMPACTS. The upper channel area of Sawan Creek is made up of three individual channels that surface from shallow subsurface flows (called interflows). Further up the slope, at the proposed block boundary, which is located about 50 meters below the proposed road location, the surface water travels sub surface. In the area of the proposed cut block and road location the terrain is made up of a series of small closely spaced parallel ridges with steeply incised draws in a parallel running pattern. At higher elevations the ridges are rocky and dry. At lower elevations there are springs developing on the small ridges. The slopes between the draws and small ridges are steep and unstable. Road construction and cut block activity would result in mass wasting and maintenance problems. The proposed road location is just up slope from where the springs surface. This is a particularly poor location as it is most vulnerable to water supply damage. The soil here is sandy-fine gravelly loam. The channel road location would cross multiple watercourses and seeps. Cutting into the surface in these locations would cause damage to the water flow, timing and quality. The normal practice would be to bring the intercepted flow into one pipe and drain down the slope. This would combine the water from several small watercourses into one on a fragile slope. By doing so the water is brought to the surface and routed away early in the season. The thus resulting high surface peak flows with erosive power in the spring cause lowered summer and fall flows, probably to the point of drying up at the water intake boxes. Bringing water to the surface instead of retaining the natural subsurface route also causes the water to be more likely to contain pathogens, Giardia and Coliform bacteria. Because Goloff Creek, Sawan Creek, Anderson Creek and Chou Creek are each made up of several drainage ways (Goloff 2-3 drainage ways, Sawan: 2-3, Anderson: 4-5 and Chou: 2), the proposed road location would potentially affect 10-13 separate drainage ways. This might seem insignificant up slope, but the year round water supply and quality of these creeks depend on each water drainage. We took special note at about site 0+809 on the proposed road location. This site would be crossing a stream watercourse. The slope is about 50% on the knob between steep incised draws and is typical of the terrain in the area. The draws are approximately ~ 0-20 meters deep with water flows during snowmelt at the bottom of the draw. Some of the springs carry a deeper supply of water than others. Sawan Creek, which has the highest spring flow and also the highest flow at the time of the field trip tour, is the one that in some areas dries up later on in the season, and cannot fully supply three water users. Anderson Creek, which has the lowest flow and the least difference between seasons, does not go dry and provides water for about eleven water users. This example is further proof of the fragile nature of the flows from these springs and of how vulnerable they are to surface disturbance.
After adding up all the impacts, my conclusion is that the proposed road construction and cut block contain too many potential hazards on a small and fragile landscape. The impact of one or the other is high, when combined the impact of both is synergistic and would cause damage to the water sources and the water supplies for many individual water users. I strongly recommend against the proposed road location and cutting block. By Allen Isaacson, Professional Hydrologist
HYDROLOGY REPORT FOR ANDERSON, ELLIOTT, CHRISTIAN, AND TROZZOby Allen Isaacson, Professional Hydrologist GENERAL OBSERVATIONS / ELLIOTT CREEK / ANDERSON CREEK
In July, 1994, Don Roht and I field reviewed the proposed road construction and cut block locations in the Elliot-Anderson watersheds. Don knows the area well and was very helpful at orientating the proposed activity sites and the relationship to the many water intakes for domestic water licenses.
We began our review in Anderson Creek where it flows under Popow Road in Lot 8254. Anderson Creek is spring. fed with a uniform year round flow. It is a stable small stream that is regulated by the subsurface flow and with a slow release throughout the year. There are no high peaks and this important water supply doesn't go dry even in the driest years. The stable flow is from different contributing areas supplying water to the stream at different times of the year. There is abundant rooted perennial moss, vegetated banks, and other indicators of stream stability in Anderson Creek as it flows through Lot 8947 and on downstream. The proposed logging block would remove the timber from the reach with surface flow in the stream, This stream channel was called a ditch at one time and was believed to be a man-made channel for water use downstream. In recent years it has been named a natural stream channel by the Ministry of Environment, and as named, is not part of a water system. This means the creek is to be protected. Our field review showed this to be a natural stream called Anderson Creek, with the natural meanders, pools and characteristics of a natural stream. Anderson Creek is not mentioned in the reports; however, we noticed that there are cut blocks planned within this watershed. The proposed activity viewed in Anderson Creek proposes using a main haul road that transverses the area where the springs are located that feed surface water to Anderson Creek. This is also an area of shallow soil and a high water table. This is the type of topography you would expect where there are many springs coming to the surface to move subsurface groundwater to a surface flow. This is the natural pattern at the toe of slopes and is the natural procedure used to form stream channels. There is a substantial flow of perennial water moving at a very shallow depth, just under the soil surface. Any road construction or skidding activity that cuts into the soil mantle will result is the disruption of the natural timing and quantity of stream flow. The human population that depends on the even year around flow will lose this valuable asset. The water will be brought to the surface in a road ditch and removed from the area much earlier in the year at a faster rate than under current natural conditions. The water supply would be routed away from the present channel and be lost to the downstream users dependent on this natural supply. The only construction practice to prevent impacting the water flow, the quantity, and the quality of the natural stream flow used for downstream water rights is with a road that is all fill, meaning that the fill has to be laid down on top of the present surface with no disturbing of the soil mantle at all. This would not be a practical way of accessing this small area. The wet areas should be avoided with any type of construction. The present road layout does not lend itself to the type of construction or location needed to prevent damage. The lower portion is all wetland and should be protected completely from any encroachment. Up the slope further in elevation above the short steep ravines the surface topography changes to a series of parallel small drainages that are spaced very close together. Tens of feet apart. Don stated that he has observed about 40 little springs in this area. The springs eventually flow together. Near elevation l000M(3250 ft) in Anderson Creek the geology is again colluvial. There are numerous stream channels. The planned upper access road crosses the creek in a wetland marsh area. This is a very poor road location. The stream meanders through a meadow at this location below one water box. The proposed lower road location crosses Anderson Creek where the stream is flowing subsurface for a distance before it again comes to the surface. The stream has a good flow through this reach, both up channel above the subsurface flow and downslope where it again reaches the surface. Any road construction would result in the water coming to the surface and an eroded surface channel downstream. This would cause a high volume of erosion, resulting in sediment being carried to the downstream water boxes and private water users supplies would be in peril. There are also several seeps out of the stream banks in this general area that contribute water volume for the downstream users. These channels should not be crossed by roads or skidding operations because they are too fragile and represent t6o much risk of damage to the downstream water users' Systems, Anderson Creek has been extended from the ditch status to that of a creek. It is recommended that these channels not be impacted with cut blocks.
Elliot Creek drainage is an interesting landform. There is a series of small flats with steep sides of talus and rock. These are not glacial deposits but colluvial talus formations. The basic landform is bedrock with a veneer of sharp talus that has not been worked(transported) by ice. or water. The steep talus and rock slopes are very dry sites; as the water is collected into wetlands, pools and small drainage ways on the nearly flat tops of little isolated benches These areas are fed by seeps and springs at the base of the dry talus slopes and form ponds on some sites. The side slopes are very dry with Ponderosa pine being dominant with dry area brush species.. The wet sites contain fir and cedar and wet. site species. The majority of the timber vo1~me is in the draws and on the little flat areas. These areas are small islands without any connections or continuity across elevation lines. They would be very difficult to access with roads for timber harvest. The draws have running water during the spring snowmelt period. As one traverses toward the south the area becomes wetter with more ponding and seeps evident. In the center of the proposed cut block area there are ponds as described above. There may be a connection of subsurface flow of water from the drainage area of Elliot toward Anderson. Elliot maybe the source of water for some of the springs in the Anderson drainage. Traveling further up slope in elevation to the proposed blocks that border the old mining claims. These blocks are laid out in the worst possible Position for any kind of protection of the downstream water supply. The plans are to cut over the headwater area of the stream where the two forks of small surface water channels meet. Geologically this is one of the most unstable sites due to the over steepening of the side slopes to keep up with the channel downcutting. This proposed block is near the location of the old mining road and cabin.
The drainages are small: Christian is 255.77 ha; Brogan is 155.8 ha, and Elliott is 195.9 ha. These are steep and active small watersheds. The planned cutting will affect 194.5 ha out of 963.9 ha of timbered land,, or a high percentage of the timber land. In the provided material from Slocan Forest Products the harvest totals have been compiled for the combined watersheds rather than for each watershed individually. Current hydrological methodology does not permit combining the areas of several watersheds and then calculating the percent that is to be cut. Meaningful numbers can be determined only from calculations within each individual watershed. In addition, calculations are not based on total watershed area, but should exclude rock and other areas that have no watershed storage capability. The percentage i~ then calculated based on the timber area that is to be cut according to 500 foot elevation bands (approximately ~50 meters). Cutting should not be concentrated in one elevation band or on the same aspect. In order to prevent damage to the stream channels, the blocks should be well scattered in elevation and on different aspects. The steep nature of these channels and their small size will make them very responsive to any activity. The stream channel average 37 % in the watersheds of Christian and Brogan and 35 % for Elliott. These are very steep channel type '~A' (Rosgen channel typing.) There is no sediment or bedload storage in this type of a channel, every. thing that goes in gets flushed out at the bottom along with a high volume of bank and bottom material that is eroded and transported along with the introduced sediment from construction or logging activities. The soils and geology are not very stable. Glacial material and colluvium are present above 800 meters elevation, with glacio-fluvial material below 800 meters elevation. The streams are incised in this material and contain many raw banks that could supply sediment with additional flow from development activity. These drainages are too small to manage for both water quality and timber production. The channel contribution area for each watershed is too small to afford the luxury of spreading the impact on different aspects and elevations. The planned cutting is to be very heavy in the lower elevations. This level of cutting can have severe negative effects in the event of rain-on-snow events and winter storms. Any road construction activity would result in negative impacts to water quality. The watersheds are too small to allow the road construction and harvest planned without an unacceptable negative impact on the stream channels and the downstream water quality I recommend that these watersheds not be logged in 6rder to be managed for water production and scenic values. |
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