Title
Entwistle - Slope Stability Assessment Along Pembina River
Proposed Motion
That administration be directed to undertake a Slope Stability Assessment, in the Hamlet of Entwistle along the east side of the Pembina River from Township Road 532 to Township Road 534.
Body
Administration Recommendation
Administration supports the proposed motion.
Purpose
To exercise due-diligence through assessment, evaluation and prioritization of potential slope stability concerns in Entwistle.
Summary
Pembina River is a major river, characterized by its deep-steep slopes, running along the west boundary of Entwistle. The river itself has carved through the underlying sandstone, shale, and siltstone formations creating a deeply incised gorge. Area residents adjacent to the Pembina River have previously expressed concerns with slope stability and the detrimental effect failure could have.
The following infrastructure exists adjacent to the river bank within this general area:
a) From Township Road 532 to Township Road 533 there is minimal infrastructure along the bank, including Range Road 74B and the Entwistle Cemetery. There are also two (2) private residents and the Pembina River Tubing business.
b) From Township Road 533 to Township Road 534 there is significant infrastructure along the bank; 55 Street, 53 Street and 52 Street, the Entwistle school property, as well as the sanitary, storm and water infrastructure. There are also several private residents situated along the bank.
The following is the anticipated scope of the high-level slope stability assessment:
1. Existing condition evaluation including;
a) Review of available geology maps and geotechnical reports;
b) Review of available topographical information; and
c) Review of historic and current air photos.
2. Site reconnaissance;
3. Engineering assessment of the existing conditions to identify areas with a high risk of slope failure; and
4. Recommendations for further study as required.
Undertaking a high-level Slope Stability Assessment will allow Parkland County to:
a) Evaluate Pembina River’s slope stability in Entwistle;
b) Identify potential public safety concerns;
c) Assess areas with high risk of slope failure;
d) Identify potential effect on County owned land and infrastructure;
e) Identify potential effect on Private owned land;
f) Determine potential causes of the slope instability;
g) Ascertain any straightforward solutions and recommendations; and
h) Identify additional study requirements if any.
Over the years Parkland County has received queries about slope stability in Entwistle. Parkland County is considerate to these concerns and recognizes a slope stability assessment will educate administration and provide framework on how to proceed with further action if required.
Strategic Plan/Policy/Legal/Staff Implications:
This request aligns with the 2016-2020 core values:
a) Responsibility: The slope stability study will identify how Parkland County can “provide quality service to residents and clients through efficient and effective practices while we undertake continuous improvement”.
b) Community: The slope stability study will help “maintain safe, vibrant, sustainable and prosperous communities by maintaining and expanding infrastructure and services".
Financial Impact:
Cost: $50,000
Source of Funding: Existing funds from Interim 2017 Budget
Other:
N/A