Understanding your bill
For this month’s post we thought that it may help to give tittle insight into the terms found on your bill.
1) Type – This indicates the type of reading that was done. It will either say actual or estimated. Estimated indicates that the meter was not accessible and that the average usage was calculated.
2) Present– The current meter reading.
3) Previous– The last reading from the month before.
4) Difference– This is the figure obtained by subtracting the present reading from the previous reading. This is your usage for the period billed.
5) Fuel Variation– The fuel charge calculated based on the price of oil. For every ten cent increase or decrease in the cost per imperial gallon of fuel purchased, APUA increases or decreases the cost per kilowatt hour by one cent. Your usage is multiplied by the current rate If your billing cycle carried into a new month and the rate has changed that part of your usage will be billed the new rate.
6) Electric Kwh Charge– The Electric Kwh Charge also known as the tariff is the charge associated with producing energy minus the fuel. Residential households are charged 40 cents per unit for the first 300 kwh they use. Any use above 300 kwh is charged at 38 cents per unit. That is why there is sometimes a second line with an electric kwh charge.
The Cost of Water
Antigua continues to experience a prolonged drought season. Currently APUA has exhausted all of its surface water resources causing sole reliance on Reverse Osmosis with a small intake from ground water. Reverse Osmosis is the process of removing salt from water. Given Antigua’s landscape sourcing water from the sea is the only option for producing large quantities of water. APUA owns two Reverse Osmosis plants and also purchases a minimum of 3.1 gallons from Enerserve. Reverse Osmosis is a very costly process because of its high energy demands. Here is a breakdown of the cost to produce water obtained via Reverse Osmosis:
Eneserve Water Cost Price $8.00/per 1000 gallons
Fuel Cost Price $8.31/ per 1000 gallons
Energy Cost $4.21/ per 1000 gallons
Total Cost $20.52/ per 1000 gallons
This cost analysis does not include the cost of treatment chemicals, energy pumping and operational maintenance which will increase the cost per 1000 gallons to approximately $30.
With these figures in mind APUA it is crucial to adopt a lifestyle of conservation.
To dredge or not to dredge?
Many persons have been querying about whether or not the dredging of our largest water catchment Potworks Dam will bring any relief in the event of future droughts. Our Planning, Standards & Customer Service Manager Mr. Hastin Barnes sheds some light on this trending topic.
“The Potworks reservoir is located in the east central part of the Island. The reservoir was created by damming an intermittent stream which runs through the area. The base of the reservoir consists of clay sitting on top of limestone. The clay layer which varies in thickness from west to east forms the seal that allows the reservoir to hold water and to minimize infiltration (leaking) into the limestone.
The public discourse on Potworks usually surrounds issues of cleaning and or dredging of the reservoir.
The question of cleaning comes up because there is the perception that there has been heavy siltation over the years. The perception that there should be siltation in the Potworks reservoir is based on the fact that rain falling on the land does cause erosion and causes soil to be washed down into streams. It is important to note however, that the rate of erosion and deposits are dependent on the nature of the surface on which the rain falls. The Potworks’ watershed for the most part is covered with vegetation. The areas with human development have paved roads. The slope of the land in the watershed is moderate to gentle. Along the stream way leading to the reservoir are a number of catchments which serves to slow down the water flow resulting in sedimentation before the water reaches the Potworks reservoir. All of the above mentioned factors have an accumulative effect of a slow rate of siltation of the Potworks reservoir. An examination of the reservoir bottom reveals that the original clay level exists in many sections. The concrete road to Bethesda can also be seen as well. Any heavy siltation would have covered that road. It is therefore the opinion of the Authority that there is not much to gain at this point from cleaning the Potworks reservoir.
Dredging is generally suggested to increase the capacity of the Potworks Reservoir. We caution against this for the simple fact that the existing clay layer forms the bottom seal for the reservoir. Removal of this clay layer would expose the limestone and cause infiltration into the ground and possible increased water loss to the sea via subsurface water flows. Alternatively, if the dredging is too deep it can also lead to sea water infiltration into the reservoir.”