SVWA releases reports by independent hydrologist on four Slocan Valley watersheds

What is hydrology?

Hydrology is the study of the distribution, flow, and quality of water. Hydrology combines knowledge from the physical, biological, and chemical sciences to look at how water systems work in ecosystems. Forest hydrology information is used in the practical application of watershed management.

Al lsaacson, independent hydrologist

Al Isaacson is a highly respected leader in the field of forest hydrology. An intensely practical man, he combines theoretical research with 30 years of experience in the field, and has co-developed models which are often cited by other hydrologists. He is an "interior" hydrologist whose specialty area is the forests of Idaho and eastern Washington. Many of these forests are similar to those in the Slocan Valley. Isaacson's years of experience can be directly applied to our watersheds.

Mr. Isaacson teaches hydrology and water management at Spokane Community College and also does contract work in the field. He was hired in the summer and fall of '93 by the SVWA to do an initial, independent analysis of the watersheds of Hasty Creek, Elliot/Anderson/Christian/Trozzo, Airy /Tindale, and Perry Ridge. His findings provide important information about Slocan Valley watersheds.

The information presented in this newsletter is a summary of Mr. lsaacson's findings. The four watershed areas discussed all have permits for road building and logging pending. Please read the following so that you can better formulate your questions for Al Isaacson at the upcoming meetings.

Hasty Creek

Mr. Isaacson reviewed several documents related to the Hasty Creek area: the Hasty/Aylwin IWMP 1990 (Integrated Watershed Management Plan - Ministry and relevant companies); the Road Permit (August 1988); the PHSP (Preharvest Silviculture Prescriptions for Blocks 1-5, August 1991); the Hasty Creek Monitoring Committee notes; and the Aspect Consultants' report of the fall of 1991.

Mr. Isaacson concludes that road building in Hasty Creek should take place "only after an analysis of cumulative effects from past activities and a risk analysis show that the area is stable enough to allow development without unacceptable damage to the slope, channel stability, and water quality. The best prescription would be no roads in the watershed." If logging were to take place, the best prescription for Hasty would be helicopter or high lead logging with no roading in the water supply basin. The next best solution would be high lead logging from the ridges with roads brought in on top from other basins, yarding the timber uphill to these roads. He is clear that no further mid-slope or low-slope roads should be constructed if water is to be protected.

The reasons? The existing road permit and PHSPs allow for excessive ground disturbing activities close to and/or within the riparian zone (alongside the creek). Due to their geologic profile, the slopes are generally wet, over-steep, and unstable immediately above the stream systems of Hasty and are particularly susceptible to mass wasting triggered by disturbance. The Hasty Creek road constructed in 1991 is located across steep, wet slopes, even though monitoring reports state that there were available easier and less damaging routes to access the same area with less distance of road and on gentler terrain. Says Isaacson,"... portions of the upper spur road in Hasty are too close to the creek, allowing for an insufficient filter area. Water intercepted by such roads is hard to control and generally finds its way to the stream along with much sediment from the road system. This will surely degrade water quality"

He concludes his analysis of Hasty by recommending that no further road-building or use of the existing roads take place until the current disturbances have healed (five to twenty years), and until appropriate restoration measures have been carried out.

Eliott/Anderson/Christian/Trozzo Creeks

The Elliott/Anderson/Christian/Trozzo systems which flow from the East into our valley have in common very steep, small drainage basins. They are of the steep channel type "A" variety which should not be crossed by roads because they are too fragile and represent too much of a risk for damage to the downstream water users' systems. This is because streams in this area are somewhat incised and contain many raw banks, from which sediment could readily be displaced, easily destroying a diversion works or water system downstream.

Planned logging will affect an unacceptably high percentage of the timber land. The calculation of the total area impacted by logging has been incorrectly calculated by lumping all of the watersheds together, and by calculating the percentage based on total watershed area. Current hydrological methodology requires calculation within each individual watershed, excluding rock and other areas that have no watershed storage capability.

Planned cutting is scheduled to be very heavy in the lower elevations. Cutting should not be concentrated in one elevation band or on the same aspect. The planned level and location of cutting can result in severe negative impacts during winter storms or rain-on-snow events.

The watersheds of this area are too small and fragile to allow road construction and logging to take place without considerable impact on the stream channels. Any road construction would result in unacceptable negative impacts to water quality. Isaacson's analysis concludes that these watersheds cannot be managed for both water quality and timber production. He recommends that they be managed for water production and scenic values only.

Perry Ridge System

Isaacson's analysis of Perry Ridge is based on his own aerial assessment plus consideration of the IWMP for Perry Ridge (June, '92), maps of operable/inoperable areas in the system; the terrain analysis commissioned by the Ministry of Forests in the mid 1980s; the water yield model (Salway report, 1985) and the Terrain Survey (Wehr, 1983); and the current map of road location. (This road location, proposed to begin at the north end of Perry Ridge, was designed more than fifteen years ago.) Isaacson concludes that none of these studies will accomplish the goal of protecting water quality, quantity or timing of flow.

The mid and lower elevations of the streams draining from Perry Ridge are very unstable and would be subject to mass failure with the increased stress of cutting in the headwaters. There may be some sites in the upper basins that are stable or flat enough to be logged. However, to get access to these areas would mean crossing unstable slopes and sensitive headwater streams.

The general geology of Perry Ridge contains shallow glacial deposits over bedrock, an unstable landform with steep gradients. It is an area which already exhibits high sediment loads during snowmelt and summer thunder storms. Unlike some ground types, the streams in this area lack natural stream sediment storage capability. An increased flow energy, which would accompany road construction or logging, would mean that considerably more erosion and sediment would be transmitted downslope. Sixty percent of Perry Ridge has a high to extreme hazard rating for sediment yield or induced mass wasting. The basins intended for logging are directly above 56 licensed water sources where there exist already many sites of natural mass wasting and avalanche paths (especially in the Talbot to Watson area).

The upper basins, where cutting is planned, are small and do not have the elevation differences needed for putting cut blocks at a wide enough spacing of elevations. Also, they are oriented to the same aspect, making it impossible to vary the aspect and decrease possible damage.

The road location begins at the north end and cuts through a steep cirque headwall in order to access mature timber - a poor choice for a road location. If the existing road-building and logging plans go ahead, Isaacson warns us that sediment and mass wasting from activity above these steep gradient streams of Perry Ridge will inevitably be brought directly to the valley floor.

Isaacson recommends against any road building or logging activity on Perry Ridge.

Airy/Tindale Creeks

The following information is based on Isaacson's October 1993 field trip during which he analysed recent and older logging activities in the Airy/Tindale area.

Airy Creek

Problems with the Airy Creek road: The existing road is predominantly very steep with not enough dips built into it to direct water off the road. Culverts do not use the natural terrain in their placement and there are no cut-off pipes to protect water quality. There are also insufficient numbers of culverts. Instead of one culvert every 200 to 300 meters as there should be, there is only one every thousand or several thousands of meters. These culverts concentrate their water directly into the streams and the road ditches are running water in many locations, having become streams themselves.

Problems with the upper basin: The upper basin of Airy Creek has been destroyed as a water storage and regulatory system. The causes are disturbance of geologic and soil functions, removal of vegetation, poor quality road construction, and timber management. For now, the stream channel, which is heavily "armoured" with large boulders, has been able to handle increases of flow. However, with the right set of weather conditions, "the whole of Airy Creek could sluice out in a peak flow event, causing damage to the Airy Creek water system and the Little Slocan River." (Airy Creek drains into the Little Slocan about 2.5 miles above the Slocan River.)

Investigating the situation in the upper basin, Isaacson saw nothing had been done to control on-site erosion to avoid accumulation of sediment adversely affecting flow rates. He found no documentation about how to handle increased water flow routed off from the main road. It is not a pretty analysis. Isaacson states poor road construction and timber management have created the potential for maximum negative impacts on water quality in the upper basin.

Tindale Creek

Due to mass failures from the Tindale roads, there have been many recent reports done on this area. All of the mass failures can be attributed to poor quality road construction. The natural conditions of steep slopes and unstable geology combined with how the cut blocks have been laid out in relation to the road system (in between and immediately above the roads) lead to the high incidence of mass failures.

When Isaacson studied Tindale in October, a normally dry time of year, the ditches were running water "as live streams." Apparently, if the ditches act as part of the stream system year round, then the fills on the road will, with time, inevitably fail.

In August of 1992, Anthony Satway stated concern about a potential slide on the east side of Tindale Creek. He said that water from several small creeks had been diverted down a spur road ditch onto a mainline road and into a larger creek resulting in excessive sedimentation and, in this case, destabilisation of a large area on a steep hillside. When Al Isaacson viewed this site one year later, no remedial work had been done. (We have been told by SFP since that this area was "seasonally deactivated" at the end of October.)

Isaacson states, "The only way to prevent damage and mass failure in this area is to prohibit future activity in the watershed or to manage the water with correct road construction techniques."

Airy/Tindale Conclusions

The two tributary systems have different problems:
sediment and water management problems in Airy, and mass failure from roads in Tindale. Below the confluence of the two creeks, Isaacson expects there will be ongoing degradation. If more mass failures are to be avoided, careful planning and engineering work is necessary prior to starting any road construction.

Isaacson concludes that there should be no more timber activity until a comprehensive plan is in place and the roads are reconstructed or removed. In Airy there needs to be some time for revegetation before any more timber removal.

Concluding Comment

In his 30 years of study, Isaacson has seen the destruction from road construction and timber cutting of many of the major river systems in the Inland Northwest. Twenty-five years ago, Americans made the same mistakes he sees us making today. In the States, many practices are currently used that help alleviate impact from road construction. These modern practices are not being used here.

Frequently, decisions about watershed management in the Interior are based on studies conducted in coastal forests, often resulting in strategies that are inappropriate for the geologically very different systems of the Interior. As the creator of some of the original models used in the field of hydrology and as an experienced field hydrologist, Mr. Isaacson understands how political realities can shape and re-shape original plans and specifications, especially where water protection rather than timber harvesting is a priority.

These summaries contain considerable technical information, though we have done our best to make it understandable. For a clearer understanding, assisted by slide photographs and time for your questions, come to the April 7 or 8 meeting.

We do know that less than 5% of the people on our planet have really good drinking water and that we in the Slocan Valley are among that tiny, lucky bunch. Water comes from watersheds and is protected by the trees that live there. We know that the older the forest, the more stable the water source and distribution and the higher the quality of water.

Come out on April 7 and 8 to learn more about the vital link between forests and water, and especially about the four watersheds scheduled for road construction and logging.

Participation in CORE continues

Both the Slocan Valley Pilot Project and West Kootenay Regional Project under CORE will continue until the end of May. If consensus is not reached at the regional table, Stephen Owen will make recommendations for land use in theWest Kootenays. Mr. Owen will submit a report to Cabinet regarding the pilot project.

Colin Mackintosh of the SVWA represents the watershed sector at the regional table. The sector has recently presented several papers to the table on guidelines and standards for water protection, risk analysis, proposed policy changes, and waterborne diseases. A further paper on water treatment systems is being prepared.

The watershed sector presented the first section of the landscape analysis contracted with the Silva Forest Foundation. Herb Hammond presented the analysis of Pedro/Winlaw Creek area on March 13. The computer-generated maps show how much old growth remains, where sensitive areas are located, and where logging has taken place. For more information, phone 226-7376.

Watch for announcements of future CORE meetings and come and check the process out for yourself!