Since my last update we changed to a different treatment chemical to reduce the possibility of discolored water and it has worked very well so far. After the New Year staff is going to try a modification of the treatment process to better control discolored water during times when there is normally a problem so they will not have to feed as much of the chemical I mentioned above. This multiple-barrier approach should make it easier for the Operators to send our customers the highest quality water during those times.
There has not been much visible activity with the studies under way to support the request for a permanent modification of the release requirements in the Virginia Water Protection permit. The transect studies wrapped up a couple of months ago and the consultant began the modeling work to determine the effects of potential release flows on the downstream river. On January 19th and 20th the final field studies are scheduled to take place which will provide the final data for the modeling effort. The flows needed for those studies are significantly lower than the normal flows this time of year so staff will have to draw the reservoir down below the spillway before January 19th to provide the needed storage to hold the excess flows in the reservoir while the studies are under way.
This is my final update to the blog as I will no longer be the Executive Director after today. I close my time here with the words Red Skelton used to close all of his shows, Good bye and God bless!
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.
Saturday, December 31, 2011
Thursday, November 10, 2011
ARWA Update
The reservoir level this morning was one-inch below (-1.0") the spillway of the Brasfield Dam. Since the hydro-electric plant is running they are releasing water for the downstream portion of the river. The most recent flow at the Matoaca gauge downstream was 568 cfs, or 367 mgd, which is equal to 4.3 inches of water flowing over the spillway.
In the Daily Data page of this blog I included the estimated inflow for yesterday from 2006 through 2011 using the current formula and the formula we were using last Summer (2010). The estimated inflow under the 1965 Hopewell Agreement is also included in that table. The inflow under the Hopewell Agreement is different than either formula under the Virginia Water Protection Permit (VWP Permit) because it is based on the average flow past the upstream gauge (Mattoax) for the past thirty (30) days. The maximum release required under the Hopewell Agreement is 155 cfs (100 mgd) while the maximum release requirement under the VWP Permit is 190 cfs (124) mgd.
The drought response triggers for November, based on days of storage remaining in the reservoir, are as follows: Voluntary (27.35 mgd) = -19 inches; Mandatory (23.85 mgd) = -92 inches; and Emergemcy (22.85 mgd) = -156 inches. This means that, if we need to call for restrictions this month we would use the fixed trigger levels of -12 and -72 inches rather than the -19 and -92 inches based on remaining storage in the reservoir.
In the Daily Data page of this blog I included the estimated inflow for yesterday from 2006 through 2011 using the current formula and the formula we were using last Summer (2010). The estimated inflow under the 1965 Hopewell Agreement is also included in that table. The inflow under the Hopewell Agreement is different than either formula under the Virginia Water Protection Permit (VWP Permit) because it is based on the average flow past the upstream gauge (Mattoax) for the past thirty (30) days. The maximum release required under the Hopewell Agreement is 155 cfs (100 mgd) while the maximum release requirement under the VWP Permit is 190 cfs (124) mgd.
The drought response triggers for November, based on days of storage remaining in the reservoir, are as follows: Voluntary (27.35 mgd) = -19 inches; Mandatory (23.85 mgd) = -92 inches; and Emergemcy (22.85 mgd) = -156 inches. This means that, if we need to call for restrictions this month we would use the fixed trigger levels of -12 and -72 inches rather than the -19 and -92 inches based on remaining storage in the reservoir.
Wednesday, November 9, 2011
ARWA Update
Today we started flushing of our transmission mains to remove any sediment or film that has accumulated or built up on the pipe walls since we flushed last Spring. We are doing this as part of changing the corrosion inhibitor we add to the filtered water here at the plant. These products bind up any remaining manganese to prevent discoloration of the water as it flows between our plant and your tap. These products also help protect the waterlines and storage tanks it flows through from corrosion. This is the first of several additional steps we are implementing or investigating to give our Operators the tools they need to remove manganese even after storm events. We will refill the storage tanks in our customers' distribution systems tonight so we can complete flushing our mains tomorrow and return our transmission system to normal function.
Monday, November 7, 2011
ARWA Update and IFIM Question
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.
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.
Monday, October 31, 2011
ARWA Update
I will be out of the office tomorrow and will not have access to update the blog. On Wednesday I will start posting the November data here and the October data will be added to the historical data on the ARWA web site.
Last week a citizeen called looking for a depiction of the water cycle or hydrologic cycle. I sent her a depiction I found at http://ga.water.usgs.gov/edu/watercycleprint.html. There are numerous depictions of the hydrologic cycle available on this website if you need them. The U.S. Geologic Survey (USGS) is a great source of water related information and I highly recommend checking their website first any time you are looking for that type of information.
Last week a citizeen called looking for a depiction of the water cycle or hydrologic cycle. I sent her a depiction I found at http://ga.water.usgs.gov/edu/watercycleprint.html. There are numerous depictions of the hydrologic cycle available on this website if you need them. The U.S. Geologic Survey (USGS) is a great source of water related information and I highly recommend checking their website first any time you are looking for that type of information.
Friday, October 28, 2011
ARWA Reservoir Levels
Yesterday afternoon Dominion Virginia Power asked the hydro-electric facility to shut down while they began work replacing three storm-damaged power poles along Chesdin Road. When they tried to restart last night they were not successful and had to wait to make repairs this morning. Similar starts and stops of the hydro-electric facility for equipment issues is why the graph below of the downstream river flows for the last seven days has such large fluctuations in flow.
Thursday, October 27, 2011
ARWA Update
One of the reasons we started this blog is to provide information to interested citizens on a regular basis so I must apologize that I have not posted anything in 7 days.
Last Thursday afternoon was taken up with Board meetings for both Appomattox River Water Authority and South Central Wastewater Authority. Since then we have been working on selecting a replacement for the boiler that provides heat to one-half of the treatment plant, the Laboratory, and the Administration offices.
The third item we have been working on since the Board meeting is the evaluation of potential products to replace our current corrosion inhibitor. We determined the current product was not as effective as it should have been in removing manganese from our finished water during recent manganese events which contributed to some customers experiencing discolored water. Changing a treatment chemical begins with looking at lots of information to make sure you select a product as good as, and hopefully better than, the current product used. That selection is followed by a lot of testing and evaluation of results to confirm the water quality is improved before we purchase the required quantities of the product.
We are also exploring two other solutions to address the elevated manganese levels in our raw water that occur following storm events. I will describe them in more detail in future posts to this blog. We will implement all of them, if they work, as multiple barriers to manganese to ensure our Operators have the tools necessary to address that issue when it occurs. Changes such as these require attention to lots of details to ensure we deliver the highest quality water to our customers throughout the effort to make the changes.
If you momitor the lake level at your property, or monitor river flows below the reservoir, you have probably noticed there has been a lot of variation in both over the past week. These variations were related to equipment issues associated with the hydro-electric facility located at the Brasfield Dam. Even with these variations in flow we always satisfied our permit release requirements.
Last Thursday afternoon was taken up with Board meetings for both Appomattox River Water Authority and South Central Wastewater Authority. Since then we have been working on selecting a replacement for the boiler that provides heat to one-half of the treatment plant, the Laboratory, and the Administration offices.
The third item we have been working on since the Board meeting is the evaluation of potential products to replace our current corrosion inhibitor. We determined the current product was not as effective as it should have been in removing manganese from our finished water during recent manganese events which contributed to some customers experiencing discolored water. Changing a treatment chemical begins with looking at lots of information to make sure you select a product as good as, and hopefully better than, the current product used. That selection is followed by a lot of testing and evaluation of results to confirm the water quality is improved before we purchase the required quantities of the product.
We are also exploring two other solutions to address the elevated manganese levels in our raw water that occur following storm events. I will describe them in more detail in future posts to this blog. We will implement all of them, if they work, as multiple barriers to manganese to ensure our Operators have the tools necessary to address that issue when it occurs. Changes such as these require attention to lots of details to ensure we deliver the highest quality water to our customers throughout the effort to make the changes.
If you momitor the lake level at your property, or monitor river flows below the reservoir, you have probably noticed there has been a lot of variation in both over the past week. These variations were related to equipment issues associated with the hydro-electric facility located at the Brasfield Dam. Even with these variations in flow we always satisfied our permit release requirements.
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