rocky ramps - latornell conservation symposium€¦ · matrix solutions inc. & rideau valley...

Rocky Ramps Managing Socio-Political

Expectations and Change to Provide Alternatives to Dams

November 20, 2019

Why Rocky Ramps? Case study – Decommissioning Haggart Island

Dams – Rideau Valley Conservation Authority What is a rocky ramp? Why a rocky ramp and how we got there?

Project process and other case studies Various steps Challenges and lessons learned

Matrix Solutions Inc. @ Rideau Valley Conservation Authority 2

Rocky Ramp

Matrix Solutions Inc. & Rideau Valley Conservation Authority 3

From: “Improving Fish Passage and Public Safety at Low Head Dams, (Schweiger, Aadland, Roarabaugh, Neast & Hoover)”, a paper presented at the 31st Annual USSD Conference, San Diego, California, April 2011: 21st Century Dam Design – Advances and Adaptations

Riffle and Pool



BEFORE: WEIR. Impassable upstream by fish or boat. Dangerous to pass downstream by boat.

AFTER: ROCKY RAMP. No obstruction to fish, canoes, or kayaks.

Before (left) and after (right) photos of a rock-ramp rapids fishway constructed at Riverside Dam at East Grand Forks, Minnesota


McFall Dam – Humber River – Bolton Ont

Location of Perth Ontario


Project Chronology 2004/05 – Feasibility Study (Ainley Group)

– Recommended reconstructing the dams in reinforced concrete

February 2007 – Functional Design Report (Ainley Group)

– Estimated cost of reinforced concrete dams = $800,000

2009/10 - RVCA field studies and hydraulic modeling to better understand upstream effects if dams were to be dismantled instead of rebuilt – species at risk in upstream reaches – potential for localized scouring of streambed


February, 2011 – RVCA & Perth opt to proceed with reconstruction in two stages – Stage 1 – replace dam at Rainbow Bridge in 2012;

est.’d cost $280K – Stage 2 – replace dam on main channel; when

funding has been raised; est.’d cost = $575K to $600K

June, 2011 RVCA hires Aquafor Beech & Morrison Hershfield for engineering services (final design, LRIA approvals, construction admin)



August, 2012: drawings and LRIA application submitted to MNR Pre-tender cost estimate = $460 to 500K (plus contingency), 65 to 78% higher than expected

November, 2012:

design process put “on hold” pending re-consideration of alternative, less expensive approaches (design costs to date – approx $35K)


January , 2013 – Perth/RVCA/MNR meeting river restoration may be a viable and possibly less expensive alternative to dam reconstruction for

• balancing flows between the two channels • supporting upstream water level • enabling fish migration • addressing dam safety issues

but would be a change from “status quo” since 1971, so effective consultation with riparian landowners and community at large is important and necessary

Rocky Ramp Concept • December 2013 -Request for Qualifications to consultants

to work with RVCA and Town of Perth staff to develop Rocky Ramp Concept February 2014 - Parish Geomorphic selected March 2014 - Team Process, Roles and Deliverables

defined July 2014 – Open House to present concept to

community – generally well received Further consultation in 2015 to work out details with

riparian landowners


Partners and Sponsors


Tay River Rocky Ramps Little Tay Dam (left) – 25 m width, 1 m height Haggart Dam (right) – 50 m width, 1.5 m height

Matrix Solutions Inc. 17

Design Constraints – Maintain access for property owners – Fish passage – Walley and White Sucker – Maximize desired flow split between the two river branches – No impact on flood elevations – Aesthetic design – Keep the public informed and involved throughout

construction – manage expectations

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Little Tay Rocky Ramp - 2015 Client - Corporation of the Township of Perth To save costs:

– No construction management – Limited supervision

Ultimately, aesthetics and uniformitiy paid the price


Council Meetings – Public Interests Enhance aesthetics of the rocky ramps Convince the public and council of concepts prior to

construction Address flow split issues and downstream impacts


Addressing Concerns Informing/reminding the public and council of project goals, discussing

cost savings, and keeping the design in context of project constraints Municipality wanted an artistic rendering of the design drawings days

before the presentation – not well received Held site meeting to discuss

likes/dislikes of the existing structure

Proposed alterations to the existing ramp and aesthetic options for Phase II

Construction Management Discussed what we can’t control

– Vegetation, log jams, debris, garbage, poaching, kayaks


What does a river look like? Dynamic Equilibrium vs. Controlled Uniformity


Andes Amazon Credit: Elizabeth Anderson

Collins Company Dam Canton, Connecticut

Phase I Alterations Success from

– Lots of communication with each property owner and manage expectations, explain limitations

– Working in the wet


Phase II – The Big One


Cofferdam Installation These cofferdams provide a clean and relatively easy

method to construct in the dry.


Field Equipment Failure Sometimes field equipment fails Ensure proper warning signs for pedestrians, close watch,

allow the bag to settle overnight before working


Then Came the Flood


Continued with the implementation of rock rows and a small low flow notch to improve fish passage


Releasing the Flood


Tay River – The Saga Continues In October of 2019 – Council meeting public concerns:

– Flow distribution between the two branches causing adverse changes (in vegetation/algae, swim-ability, water quantity, etc.)

– To be continued..


Nepean – Heart’s Desire Ramp Rideau Valley Conservation Authority – Construction 2018


Cobourg – Caswell Dam Ramp Ganaraska Region Conservation Authority – Construction 2018


Multi-Functional Design


rocky ramps - latornell conservation symposium€¦ · matrix solutions inc. & rideau valley...

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