Acid Rain Mitigation Project

In 2009 the Mersey Tobeatic Research Institute (MTRI) prepared a report for the Nova Forest Alliance and Environment Canada that identified eleven possible sites within the Gold, Lahave and Medway watersheds where terrestrial liming could take place (MTRI 2009). This study made tentative conclusions about candidate sites but recommended further data collection and analysis. This report attempts to fulfill those recommendations.

To view the full MTRI report for this project in PDF format, click here.

The Medway River Salmon Association has developed its own business plan to handle this project.  It is an evolving project and, as such, will be regularly updated as new information becomes available.  This particularly relates to new information pertaining to project costs, revenue sources and progress made in generating new partnerships.

To view the full MRSA business plan in PDF format, click here.

Both PDF documents are large.  Depending on your internet link, they may take some time to download.

See also:    Liming restores Atlantic salmon (Salmo salar) populations in acidified Norwegian rivers
by Trygve Hesthagen, Bjørn M. Larsen, and Peder Fiske
The Economic Viability of Lime Dosing in Nova Scotia
by William J. Daniels, St. Francis Xavier University


In the fall of 2013, Bluenose Coastal Action Foundation worked with MRSA volunteers to survey 5 stream tributaries on the Medway River.  Click here to find the written report on the results of this study.  The study was funded from a $10,000 grant from Habitation Nova Scotia.  Over the winter months Brain Dulude, Project Manager, has submitted applications for three more projects for the coming 2014 season.  If we are successful, we will be purchasing limestone and hiring manpower to distribute the product at the locations indicated in the report.  As we move forward it is very important that we continue the work our association has started to better understand the health and well being of The Medway River.

Horace Macpherson President MRSA


MRSA Terrestrial Liming Projects in 2014

Fish habitats in Southern Upland watersheds have low pH water, the lasting effects of acid rain.  Without raising pH in the streams, salmon and brook trout fry are doomed to survive low pH events, in particular, the low pH in snow melt just as the fry emerge. Terrestrial liming is spreading limestone over the surrounding land near a stream where it dissolves into the groundwater flowing into the stream.  This provides a long term (6 to 30 years) buffering agent to continuously raise the pH of water in the fish habitat.

pH and Temperature Study

In the fall of 2013, Bluenose Coastal Action Foundation worked with MRSA volunteers to survey five stream tributaries into the Medway River. They found good to excellent fish habitat but also they and Adopt-A-Stream identified four concerns:  low pH water, too warm summer temperatures, the presence of smallmouth bass and potential high aluminium content in the water.  As the next step, we applied for a $14,800 project from AAS to further study water pH and temperatures in four streams, using data loggers to continuously measure and record during 2014. Our commitment is to install the data loggers and to have trained help to monitor the water quality (ground truthing).  If pH can be showed to be the sole limiting factor, then this work leads into a proposal to apply terrestrial liming staged over years into the selected streams. 

Terrestrial Liming of Tumblingdown Brook

Tumblingdown Brook flows with cool water at about 5.3 pH, with no invasive species present, and so it would very likely benefit now from terrestrial liming.  To get started, we applied for a $44,400 project from AAS and DFO where 60 tonnes of limestone would be applied on private land near the headwater.  Included in this effort would be to complete pH monitoring and aluminium testing in early 2014 to further prove the brook’s suitability.  The main work of purchasing limestone and spreading would be done in the summer with a hired temporary manpower and our volunteers to manage and supervise the job.  A sign would be posted to promote the sponsors on Medway River Road near the brook.   

Terrestrial Liming at Twin Bridges

MRSA and Bowater Mersey Paper Company did 30 tonnes of terrestrial liming at a 20 ha site near Twin Bridges on the Medway River in 2010.   The site may be secured for long term use through the Medway Community Forest Initiative.  We have applications in progress for $66,150 from WWF Community Water Fund (Loblaws) and Nova Scotia Power Community Funding.  Mersey Tobeatic Research Initiative, who was previously involved with us on this site, is willing to provide expertise and in-kind help with data collection.  This project would require 60 tonnes of limestone.  We would monitor the results for 5 years with data loggers, with MTRI help to ensure good procedures.  The main work of purchasing limestone and spreading would be done in the summer with a hired temporary manpower and our volunteers to manage and supervise the job.  Travel to this more remote site poses a difficulty.  A sign would be posted to promote the sponsors near the bridge near the former BMPC camp.

Path Forward

The cost of the possible three projects in 2014 totals about $118,000. The cash from the sponsors would go to purchase limestone and to hire manpower for the hard work to spread the limestone at the sites.  

Our commitments would be for in-kind volunteer work in several activities: 

  • Committees to plan the work – 5 persons X 15 hours
  • Purchase and ensure limestone delivery – one person X 3 days
  • Layout the sites (200 flags to mark each deposition) – 2 persons X 5 days
  • Promote the projects on our website and in the newspapers –a person X 20 hours
  • Supervise the limestone spreading – two persons X 9 weeks
  • Transport the hires to site, especially long trips to Twin Bridges – vehicles and driving – two persons X 9 weeks
  • Organize and install data loggers on several bridges – two persons X 3 days/year for 5 years
  • Monitor and guide trained individuals to ground truthing the data loggers – a person  X 30 days  (or two persons if we are trained ourselves)
  • Keep track of the in-kind contributions and the project spending for future audits by the sponsors – a person well organized over 2014
  • Organize and publish project results to satisfy credible scientific reviews – a person well organized over 5 years
  • Build a machine to spread limestone in forested boggy land – two person X a week
  • Install two signs for the sponsors – purchase permanent signs, install posts in ground – two persons X 3 days

To be sure, terrestrial liming is hard work requiring persistence to see it done to the end.  To keep our sponsors involved, we must show the work completed and then show how the water quality and fish habitat were restored for long term results.

Brian Dulude

January 14, 2014


On September 10th eight members of the Environment Committee went to Twin Bridges (Bowater Property) and spread 28.7 ton of pelletized limestone over the 4 hectare site. The stone was delivered a week earlier by Anthony Trucking of Mill Village. This is part of a larger project to lime 20 hectares at the same site.

Studies indicate if you lime land to the tune of 10 ton per hectare you will receive a 25 year benefit to the soil and ground-water. In the instant case the land was limed with 7 ton per hectare so the result should be somewhat less. Liming of the land base in the Southern Uplands, especially in Queens County, is extremely important as the buffer zone has been diminished by Acid Rain over the past 50 years.

It had been hoped to lime the full 20 hectares, however, financial support from the Nova Forest Alliance and N.S. Forest Products Association was not forthcoming. This is unfortunate as the forests stand to benefit more than the water with the increased pH. The results of the Twin Bridges Pilot Project would have provided scientific information for the future on large scale land based liming initiatives in the area/province. The Mersey Tobeatic Research Institute of Kempt has taken pH readings prior to and will monitor the results over the next several years.

The shovel and bucket brigade, who spread the limestone, now understand why it is recommend to aerial lime forested/woodland areas.

UPDATE 04 MAY 2011

Yesterday saw the release of unfed fry in the upper reaches of West River. The following note received from one of the members involved passes on great news about the success of our liming efforts.  The photos he sent also tell some of the story.


The release of 47,000 unfed fry yesterday went extremely smoothly.  It was not an easy task for the ten volunteers who made it happen–canoes, unfed fry and volunteers had to be trucked into a remote location via an ATV, from there three canoes were sent down river 4km to release the fry in to what we thought were habitat voids.  That was the big surprize – wild atlantic salmon beat us to this area!!!

While volunteers waited for the fry to arrive, some did some trout angling and caught smolts just below the falls on the upper end of West River!  This top 10km of West River has been void of salmon since the 1970’s.  The pH in this area is now 7.   Finding salmon smolts at these falls (this is as far as salmon can travel on the West River) is huge news!!!

It means -liming works!!!! it means we have salmon production in an area that has been dead for 40 years!!!!! I think it’s time we start making some noise about liming.

The smolt count is also getting exciting this year; after only our first week of counting smolts the estimate for the first week is 1875 smolts!!! and we don’t expect the smolt run to peak until May 10th–and we now know that we still have smolts 30km up river.

Can you tell that I’m excited???

George  Ferguson (VP, NSSA)