In reaching my decision on an AAC for TFL 45, I have considered all the factors presented above and have reasoned as follows:
The base case harvest forecast shows that a harvest level of 220 000 cubic metres per year (approximately 5 percent above the current AAC of 210 000 cubic metres per year) could be maintained for one decade before declining by 10 percent per decade for 2 decades, and a further 6 percent after the third decade, to reach 167 000 cubic metres per year. This level is maintained for 7 decades before increasing over 2 decades to the long-term harvest level of 185 100 cubic metres per year. This forecast conforms to the principles discussed in 7(3)(b) above, regarding the transition from old- to second-growth harvesting, and based on my review of implications to the province of alternative harvest rates, lies within an acceptable range of harvest forecasts for TFL 45 at this time.
My considerations have identified a number of factors that exert either upward or downward influences on the timber supply projected in the base case and that were not accounted for in the base case forecast, due to changes in practice or information since completion of the analysis in January 1996.
Factors exerting a downward influence on timber supply and reducing the length of time the initial harvest level can be maintained include:
On the Interfor maps, some of the wildlife habitat areas have been shifted by approximately 50 to 100 metres from their actual locations in the high-productivity valley bottoms to lower-productivity uphill sites. This mapping error was incorporated into the timber supply analysis and represents a small, unquantified downward pressure in the medium to long term;
The analysis did not account for riparian management zones now required under the Forest Practices Code. This represents a 2 to 3 percent downward pressure on timber supply over all time frames; and
Provisions under the Code for stand-level biodiversity decrease the volume of available timber by approximately 2 percent over all time frames.
Factors suggesting the timber supply may be greater than projected in the base case are:
The site index of cedar stands (other than those between the ages of 41 and 140 years) have been underestimated, and as a result, medium- and long-term timber supply is higher than indicated in the base case. It is also likely that the site indexes of all other species (excluding stands between the ages of 41 and 140 years) have been underestimated; however, the amount of underestimation has not been quantified with any certainty at this time. This represents an additional unquantified, but potentially substantial upward influence on medium- and long-term timber supply beyond the impact of increased cedar site indexes.
Small changes in the forest cover requirements applied to visually sensitive areas have a significant impact on timber availability, and large increases in timber supply can be gained in the medium term if requirements for visual quality are moderately reduced. In addition, the use of partial cutting harvesting systems in visually sensitive areas may allow for harvesting of greater volume in these areas than might otherwise be expected. Considering the Minister's memorandum discussed above, I conclude that allowing for less restrictive forest cover requirements in visually sensitive areas represents an unquantified upward pressure.
The downward factors represent an immediate decrease in timber supply of approximately 5 percent. BCFS staff indicate that even if timber supply were decreased by this amount, the initial harvest level projected in the base case could still be maintained if a more rapid rate of decline, such as 15 percent per decade, were acceptable. Sensitivity analysis verifies that the short-term harvest levels projected in the base case can still be attained with a 4-percent decrease in the size of the timber harvesting land base, which I consider to be a reasonable approximation of the impact of overlapping riparian and biodiversity requirements. From this, I conclude that even without taking into account the upward influences on timber supply, a harvest level of 220 000 cubic metres per year can be maintained in the short term while allowing for a reasonable transition to long-term timber supply levels.
If the information described above indicated that the projected initial harvest level, which represents an increase of 10 000 cubic metres over the current AAC, could only be maintained for one decade, I would not provide an AAC increase. However, adjustments in the management of visually sensitive areas could provide significant flexibility in the timber supply of TFL 45. Sensitivity analysis shows that if the allowable disturbance is increased in all management zones, the initial harvest level projected in the base case can be maintained for 4 decades before declining to a long-term harvest level higher than in the base case. On this basis alone, I am satisfied that the projected initial harvest level can be achieved for longer than the one decade forecast in the base case. However, site index adjustment represents an additional, and significant, upward influence on timber supply. The analysis shows that if site indexes for young and old cedar stands have been underestimated, medium-term timber supply is increased over that of the base case. Furthermore, if site indexes for other species (excluding stands between the ages of 41 and 140 years) are increased by 3 metres, then the initial harvest level projected in the base case can be maintained for 6 decades. As discussed above, there is no conclusive statistical basis for the 3-metre increase; however, I cannot ignore evidence presented to me from other coastal areas of the province which indicate that the estimate used in the analysis is reasonable and likely conservative for this management unit. While I would hesitate to apply site index increases on their own, I believe they add extra support and flexibility to the upper pressures afforded by other factors.
Considering the upward and downward influences discussed above, I believe it is likely that a harvest level of 220 000 cubic metres can be maintained for at least several decades. As discussed in the considerations, there is also potential to provide additional flexibility in future timber supply through enhanced silviculture and related reductions in minimum harvestable ages and regeneration delays. From the foregoing reasoning, it is my determination that a timber harvest level that accommodates objectives for all forest resources during the next five years, that provides for requirements of the Forest Practices Code as they are currently implemented, that ensures longer-term integrated resource management objectives can be met, that meets provincial objectives and that avoids disruptive shortfalls in future timber supply, can best be achieved in this TFL at this time by establishing the AAC at 220 000 cubic metres.