6.d) Staff Report-Log House LandingStaff Report
To: Park and Recreation Committee
From: Tim Kieffer, Maintenance Superintendent
Date: January 7, 2013
Re: Log House Landing
Agenda Item #: 6.d)
Background:
Committee members would like to install a sign at the Log House Landing. Staff has been
working with the watershed district to come up with erosion control solutions for 205th St. N. and
the Landing. The designs are preliminary and most likely will change. Grant money will help
fund some of this project. Therefore, a project will not take place until 2014 at the earliest.
Proposal Details:
Attached is the preliminary design from the watershed
Fiscal Impact:
Unknown
Options:
1) Make a motion to further discuss installing a sign
2) Make a motion to wait until erosion controls are in place
Recommendation:
I recommend waiting until erosion controls are in place to prevent damange or relocation of the
sign.
651 Hale Avenue North Oakdale, Minnesota 55128 telephone: 651.770.8448 facsimile: 651.770.2552 www.eorinc.com
Date I November 8, 2012
To I Jim Shaver, CMSCWD Administrator
cc
From I Carl Almer, Brad Aldrich, Jay Hill
Regarding I Loghouse Landing Erosion Control & Water Quality
Concept Design Solutions
Issues
The issues identified during a site visit on October 12, 2012 centered around erosion of the steep gravel
access road to the landing. Gravel is washing off the road and traveling down steep slopes of a ravine to
the adjacent stream. A portion of the runoff flows down the hill and erodes the landing and parking areas
in certain areas. The resulting gullies and rills in the roadway continue to deliver sediment to the stream
and St. Croix River, and require constant maintenance — which involves adding more gravel material, that
is subsequently washed out in the next storm event.
This continuous cycle of erosion and repair have led to a visible trail of sediment leading from the
roadway into the adjacent stream and river. The steepness and length of the access road's slope, class V
gravel material of the drive, and relatively high summer weekend traffic create a difficult problem in a
high quality natural and recreational setting.
Concept Design Solution
This highly complex site will require additional investigation and engineering design to provide greater
detail to the proposed solution. However, the attached feasibility study graphic and cross section
illustrate a general approach that rebuilds the cross section of the road in order to slope it away from the
steep ravine to the south. The road grade would direct water into a heavily armored swale along the north
side of the road. Two BMPs could be integrated into City owned property adjacent to the road including:
A. A linear, infiltration feature halfway down the slope. Concept linear nature would minimize
damage to mature white pines. Overflow would be dispersed across the slope and be allowed to
soak into downslope areas.
B. A bio -filtration facility located in the existing "no parking" area at the bottom of the hill.
Overflow and filtration outlet would be in a controlled outlet to the river.
Both facilities would require pretreatment infrastructure that would deliver runoff in a controlled manner
and provide easy access for maintenance. Utilizing two facilities helps split the watershed treatment area
into two manageable segments. If only one facility was provided at the bottom of the road, it would be
exposed to a significant volume and velocity of runoff due to the road's steepness and length. This would
require significant area to control and treat the runoff, and increase the risk of failure in large storm
events.
The existing class v road surface will also need to be modified. Future design work should evaluate
options of using asphalt across the entire cross section of the road, a cellular confinement grid with gravel
or vegetation, or a combination of the above materials. One potential solution is to use a cellular
confinement grid with clean gravel for the parking lane, and asphalt for the road itself. The goal is to
An Equal Opportunity Affirmative Action Employer
Emmons & Olivier Resources, Inc. water I ecology I community
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provide the cleanest, most controlled runoff flows to the rock lined channel, and provide some volume
reduction if possible. The rock lined channel conveying runoff to the two proposed Bws would have
check dams to slow water down and encourage modest infiltration.
Using a traditional curb and gutter in place of the rock -lined channel was also discussed. This option
would potentially allow more parking, but would also be more costly (due to the amount of infrastructure
that would be required), and would provide less water quality benefits. We feel that limiting the road
width available for vehicles would limit the landing to a smaller, more neighborhood -centric river access
point.
Additionally, some regrading and stabilization measures near the boat ramp would correct existing
erosion issues. However, these issues are minor compared to the roadway erosion problems.
The attached graphic and cross section provide a graphical representation of the design approach for the
Loghouse Landing. A preliminary estimate of probable cost to stabilize the Loghouse Landing,
implement rate and water quality treatment BMPs discussed above and reconstruct 205` Avenue North to
reduce or eliminate the existing sediment source is approximately $180,000.
Emmons & Olivier Resources, Inc.
651 Hale Ave N. Oakdale, MN 55128 p: 651 770 8448 f: 651 770.2552 www eorine corn
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