Today I read all of our irrigation water meters and revised all of the sprinkler system settings. A second watering cycle was added in the middle of the day and all of the overnight cycle start times were moved earlier (some as early as 9:30 PM) so they all finish before 6:00 AM when the pressure in the Shelby Twp. system begins to drop. To view the revised sprinkler system settings, click here.
Between April 21st and today, all of the meters feeding the sprinkler system have delivered 3,678 units of water (367,800 cubic feet). At $2.873 per unit, that comes to $10,576 worth of water, which is about one-third of our 2010 budgeted amount for municipal water. Over those 75 days the system actually watered about 51 times, due to the rain sensors, a couple of weeks of every other day watering, etc. So basically, it costs the Association about $207 ($10,576 divided by 51) each time we run all of the zones in the Manors. With a second watering cycle, our daily cost becomes about $400.
Based on our water consumption to date, I did some calculations to determine how many days we can afford a second watering cycle:
$33,000 - 2010 Budget line item for municipal water
($10,567) - spent to date (one cycle per day)
$22,433 - line item balance
($12,740) - projected spending through Sept. 30 (one cycle per day)
$9,693 - available for second daily watering cycle
$9,693 will fund 47 actual days with a second daily watering cycle, so we should have enough budget to water twice a day for the next 6 to 7 weeks, if necessary.
In 2009, we watered for 20 weeks (May 21st through Oct. 7th) at a cost of $33,000. On Jan. 1, 2010, Shelby Twp. increased our water rate by 9%. To make matters worse, this year we had to start watering on April 21st because of the warm and dry spring. But with careful monitoring and some stingy watering during the past 10 weeks, it looks like we can afford to water 23 weeks this year (up to the traditional Sept. 30th shut-down date) with the more expensive water and still come in at the same total cost as last year.
I'm sure you've noticed lately that the Shelby Twp. water pressure has been very low between the hours of 6 to 9 AM and from 6 to 10 PM. The heads on our sprinkler system requires a minimum water pressure of 35 PSI to operate properly and provide sufficient overlap.
UPDATE: Using a pressure gauge to measure the actual pressure being maintained by the Shelby Twp. water system, I observed that it was below the 35 PSI minimum from 8:00 PM through 10:30 PM on July 6th, bottoming out at 27 PSI around 9:00 PM. At 6:15 AM on the 7th, the water pressure was even lower at 20 PSI and it didn't reach 35 PSI until 9:00 AM. It reached the normal pressure range of 50+ PSI at noon.
With the revised watering schedules I have tried to avoid watering during those low pressure time periods, but it is impossible to do so on Controllers 1 and 2 (serving addresses on Lexington South and Central Park North). That is due to the fact that all zones on these two controllers are hooked up to the same water meter and must run sequentially for 13.5 hours to complete one cycle.
