This past Summer the frequent storms helped keep Lake Chesdin filled most of the time also brought us increased manganese levels that had to be reduced to prevent discolored water. I am sure that most of you know we were not always 100% successful at doing that last Summer so we are working on several approaches to deal with manganese in the future.
In terms of raw water we are investigating the feasibility of aerating the reservoir near our intakes to discourage the growth of algae that can cause taste and odor issues and keep the manganese in a form that is more easily removed by our treatment process. We currently oxidize the organics in the raw water and we are installing a treatment point to further oxidize any manganese remaining after the settling basins.
After filtration we treat the water further to keep any manganese left from causing discolored water between our plant and your faucets as well as help prevent corrosion in any pipes it passes through. We are looking at alternative products to use that better serve those purposes.
Before we start feeding the first, and hopefully the last, alternate product we are going to flush any settled material from our mains so we start with the cleanest pipes possible. We flush our mains every spring before higher Summer demands can stir up discolored water so this will be the second flushing this year.
We hope these efforts will provide us multiple barriers to more effectively reduce the manganese that leaves this plant in the finished water. We will not need to use all of them all the time but they will be there to help us when we need them.
At the October 2011 ARWA Board Meeting, Mark Krueger, a resident of Dinwiddie County, asked for clarification about something he read in our IFIM Study Plan. His concern was about one of the species of concern that the Virginia Department of Game and Inland Fisheries (DGIF) included in the habitat suitability analysis of possible releases from the reservoir. He wanted to make sure this was not a new species that was not present in the river now. He also had questions about the amount of water required to provide suitable habitat for this species.
With the help of our consultant performing the IFIM study I shared the following response with Mr. Krueger:
- The speices in question, American Shad, has used the James River and its ributaries in the past but they are not capable of getting past dams or similar structures in the rivers if they lack fish ladders or other similar devices. DGIF has been working for years to restore American Shad to the James River and its tributaries by removing structures and providing ways for them to get past remaining structures. Those restoration efforts are working so DGIF wants to make sure American Shad are included in the habitat suitability analysis for the Appomattox River.
When I looked at the figure in the study depicting the preferred water depths for American Shad it also appeard to me that they needed deep water during their juvenile stage. I concluded they would live in the reservoir or in deeper portions of the rivers during that stage. The consultant explained to me, however, that the figure was intended to show that American Shad prefer water 1 to 2 feet deep during the juvenile stage of their life and the deeper water is less desirable.
I appreciate Mr. Krueger asking his questions so we had the opportunity to clarify the information presented in the Study Plan. We look forward to more exchanges of this nature in the future as the project moves forward.
The Appomattox River Water Authority was formed in the 1960s to own/operate a regional water supply and sell drinking water to the cities of Colonial Heights and Petersburg as well as Chesterfield, Dinwiddie and Prince George counties. The information below is updated frequently to communicate current information on Chesdin Reservoir and its environment.
