The Geotechnical View
The geo-physical ability of the site to support development is critical. Geotechnical assessments were developed by Hamilton & Assoc. in 1994 and by AMEC in 2009. The latest assessment consisted of the following components:
- Site Stability Analysis – Seismic Refraction Survey: This analysis consisted of series of 6 explosive shots interpreted by a line of sensors spanning the site;
- Composition Analysis – Penetration Testing: 29 bore holes were drilled at strategic locations on the site to determine the composition of the substructure;
- Ground Condition Analysis – 33 test pits were dug in key locations to determine the soil conditions and moisture content; and
- Geological Hazard Assessment.
The Geotechnical Analysis determined that the site is mainly comprised of gravelly, sandy, stony and clay marine and glacier deposits, covered in approximately 300mm of topsoil. It also confirmed the integrity of the site and the absence of glacio-marine clays.
The engineers have suggested that engineered footings be considered for structures along the waterfront to protect against possible liquefaction and that slopes be stabilized on a structure-by-structure basis. They also included recommendations for cut and fill, back fill and foundation designs.
Engineers from AMECFW (formerly AMEC) have been back to verify the site in recent weeks and have concluded that these findings remain valid.
The Environmental View
The Plan has been developed to minimize the environmental impact. Environmental Assessments were conducted by Pottinger, Gaherty in 2004, and by Cascade Environmental in 2005. Cascade was re-engaged to update their assessment during the last few months. This Plan is based on the findings of these assessments.
Scientists first checked existing maps and aerial photos to determine the “ecological units” that would form the basis of their assessment. Based on this they conducted multiple transects across the property being certain to touch on all of the ecological units.
Historical analysis showed large scale logging of old-growth around 1890 plus a second round of tree harvesting during the 1950’s. Gravel operation impacts from late last century were noted in two locations as was selective logging in the early 2000’s.
The site analysis found one major riparian system along Shannon Creek, plus a minor one along Angus Creek near the south-east perimeter. Despite repeated site exploitation, both riparian zones were found to be intact and will need to continue to be protected in accordance with BC’s Riparian Areas Regulation, including the May 2006 Amendment.
No red-listed (endangered) or blue-listed (special concern) wildlife was found on the site. While none were observed, the riparian areas were considered to be an appropriate habitat for the (blue-listed) Coastal Tailed Frog.
Despite the timber harvesting, selected veteran red-cedar, big leaf maple and western hemlock trees were detected. These, in addition to a recently discovered veteran Yew tree, will be protected in this Development Plan.
Cascade Environmental’s new assessment confirms these original results.
The Storm Water Management
A storm water management analysis was conducted by AMEC (currently AMECFW) in 2006. The analysis consisted of hydrologic modeling based on historical data. The impact of replacing pervious land with impervious materials normally used in roads, parking areas, driveways, roofs, decks was assessed, based on both 5 year and 100 year meteorological returns.
The scientists concluded that the gravel and sand composite substructure is excellent for natural returns to aquifer. They recommended a catch basin plan be implemented at the time of development, and that low-impact development, as proposed in this Development Plan, be considered.
The Traffic View
Traffic studies were conducted by Hamilton & Associates in 1997, and by Bunt in 2005. The 2005 analysis was re assessment on behalf of the District of Sechelt by Binnie & Associates in 2007. These included physical surveys of the road geometry, a traffic background study (21 April 2015 volume plus 20%) and traffic modeling (Friday 4:00-5:00 pm and Saturday 2:15-3:15 pm). Of special significance was the anticipated high concentration of traffic at specific times from the 18-hole golf course.
The analysis forecasted minimal delays (MOT Level of Service A) at existing traffic levels, and that this would continue to be the case even including the augmented volumes resulting from the completion of 800 new homes, 1,500 m2 of additional commercial space and a 40 room hotel plus the (no-longer proposed) 18-hole golf course. Mainly due to the anticipated heavy weekend volumes from the then-proposed golf-course, the engineers suggested that signals and a left turn lane at the intersection of East Porpoise Bay Road and Wharf Road would be helpful. They concluded that there would be only minimal impact from moderate development.
The analysis showed that material impacts on the level of service (MOT Level of Service B) would not occur until the full complement of 1,600 homes, 3,000 m2 of commercial space, a 120-unit hotel and the golf course was built. This Development Plan does not contemplate this level of density.
Binnie & Associates has been engaged to update their assessment for the District of Sechelt, immediately upon approval of the Rezoning Bylaw reflecting this Plan.
Experts from Binnie & Associates have reviewed this Plan and have been engaged by the District of Sechelt to provide a formal review of their previous work prior to final approval of by Council.
The Archeological View
Archeological elements are important values that need to be recognized and protected. I.R. Wilson Consultants completed an archeological examination of the development site in 1995, under Heritage Conservation Act Permit 1995-224. The assessment was conducted in consultation with the shíshálh Nation.
High potential yield areas were determined based on a review of 36 pieces of historical literature. A team of 2 specialists transected the foreshore, creek beds and higher elevations, which were identified as the high potential areas. Their search focused on ethnographic evidence of the presence of Native Indian, European, Euro-Canadian or other ethnic affiliations, with special regard for the shíshálh heritage.
The archeologists found that repeated logging and gravel extraction had disturbed a large portion of the property. Since most, if not all, of the old growth trees had been harvested in 1800’s they felt it unlikely that any Culturally Modified Trees would be present. They did not find archeological evidence in the riparian areas, nor on the man-made foreshore, which was constructed of 3 metres of fill and gravel during the last 50 years.
The archeologists concluded that there is little likelihood that archeological values would be disturbed by development on the Site.
In April of 2016, another archaeological examination was performed on the SSC Property by In Situ Consulting based out of Roberts Creek in collaboration with the shíshálh Nation. The SSC team was permitted to be present during the survey and, as a result, learn a lot about the shíshálh Nation history in the area. The shíshálh Nation history is fascinating and although the results of the search for ethnographic evidence during this survey was similar to the one performed previously by I.R. Wilson Consultants, the SSC Properties Team was excited to have been a part of a great learning opportunity.
The Marine Ecosystem View
Since the foreshore area of the development site holds ecological and aesthetic value, Pelagic Technologies was engaged to provide a comprehensive marine survey in 2014. This included an initial reconnaissance dive to determine bottom conditions followed by multiple, detailed inter-tidal and sub-tidal transect swims at 15m intervals.
The study found a continuous 3m wide band of eelgrass about 10m from the high, high water mark, with densities of up to 81 plants per m2. Perch, Sculpin, Sea Stars, Red Rock Crabs and Hermit Crabs were found within the eelgrass. No species at risk were observed during any of the dives.
Based on the Pelagic assessment, this Plan recognizes the need to protect the eelgrass. We will require that all structures traverse over the eelgrass to minimize disturbance and over-shadowing, and only non-VOC materials will be allowed in the vicinity of the beds. Furthermore, a “Green Paddling and Boating Centre Protocol” is being developed to maintain a level of ecological integrity in the foreshore area.