Our trip to Gold Beach
They have the neatest water system in Gold Beach, proven by mother nature and it has been working since the 1950s, cost is exactly what Shady Cove can afford.
Gold Beach's "rainy well" provides clean supply of water
By Melissa Martin for the Mail Tribune
Gold Beach is the last city along the Rogue River that draws and treats water. But it's not getting the leftovers, thanks to an efficient collection system.
This coastal town pulls in 1.2 million gallons a day in the summer for it's 1300 customers using an infiltration gallery installed in the 1950's. Rather than sticking a pipe in the river the way the other cities do, Gold Beach has a "rainy well," a cast iron pipe buried beneath a gravel bar.
" Originally, it was 10 to 12 feet deep, but now as the surface has become more shallow, it's about five to seven feet below the river. " said Jeff Denney, Gold Beach's superintendent of public works.
The buried collection pipe is perforated and has a layer of sand on top that naturally filters the water, Denney said. The state labels this " ground water under direct influence," and Gold Beach holds a water right of 9.2 cubic feet per second.
The water has been so pure that the city until recently only had to add chlorine and pipe it to households, Denny said. But last spring, Gold Beach built a treatment plant to deal with turbidity, a cloudy look that can interfere with chlorination.
The advantage of the underground collection system is that the city has a consistant, clean water source year-round, while cities that draw from the river's flow fight muddy water in the winter and high algae content in the summer, he said.
" It's a mother nature filtration system," Denny said.
" I hear people say, 'You are at the end of the line after Medford, Rogue River, and Grants Pass dumping their treated sewage into the river. But with this system, our water quality is excellent. And all of our tests results show it."
Gold Beach, questions and answers :
A. The cost of the Gold Beach Filtration plant was $1,040,000. It does not use gas chlorine, which we must avoid. The best is 'OCG' Onsite Chlorine Generation.
yearly Costs: operator $40,000, Chemicals $15,000, electrical power $35,000
GB sewer customer bill is 12.75 per month
GB uses a Roberts filter system, works very good because of low maximum turbidity
For Turbid water, Micro Flock filter works best. i.e. Joe Carlone Rogue River water tech.
EMK built the plant, a very good Eugene contractor, but is retired now!
2 parallel 8 inch 75 HP pumps move water from plant to city.
1. What is the minimum depth of an intake pipe and still function with clear water intake?
Empirically, at 10 to 12 ft depth, turbidity was not a problem, now at 5 to 7 ft in depth, the filtration plant was built to remove turbidity during high river flows in the winter.
2. Where is sea level in relation to the intake pipe? My estimate, 50 feet
3. How many feet of intake pipe per gallons of water intake? Observed a drawing with "96 feet" This appears valid as example, a vertical well, 200 ft deep with a solid water level at 100 ft. If the bottom 100 ft were perforated and with the right sized pump could produce 1000 gpm.
1.2 million gallons a day, that's 833 gallons a minute. Is this a steady flow into a storage facility or is there a peak pumping capacity when demand is higher?
A pair of pumps (parallel for back up) move water from the upstream buried collection pipe to the plant input. Perferated collection pipe is 18 inch in diameter and then water is pumped to plant 500 feet down stream via a 12 inch pipe.
Article stated 1300 customers, is that Households ie. is it about 3000 population?
That comes out to 400 gallons per capita, that is quite high? --- 3300 population served
This is explained by the very large motel/tourist trade, the low cost of water usage for irrigation and a large volume of water used for water plant back flushing and maintenance. Cost per household in the city is $10 to $20 per month depending on usage. For people served outside the city it is $20 to $40 for comparable usage.
4. Could a pipe be drilled through a gravel bed rather than trenched.
In Gold Beach it was trenched which could be accomplished in Shady Cove. Alternately it could be accomplished as below: ( Vic's proposal--VP)
ie. a 18 inch perforated pipe drilled 10 plus feet below a gravel bed and across the river. This 18 inch pipe now filled with sand for filtration. At each side of the river very pure water could be drawn as required. Back flushing could be accomplished from stored water.
What size are the perforations?................. On outside 18 inch pipe?..............
From a usual kitchen faucet 3 gallons a minute can be drawn. Estimate 1/4 inch oriface, lower pressure, 1/2 gallon per minute. 1 cubic foot (8 gallons), per second of water, Shady Coves' requirement.
8 X 60= 480 gallons per minute SC water requirement. ie. 960 1/4 in perfortations required. Times 2 for safety, 2000 1/4 inch or equivalent.
The perforating tools used in normal vertical wells could be adapted (VP)
We could drill across the river in Shady Cove and draw water from both sides as there is water demand on both sides. (VP)
5. Since the 1950s, has there been any maintenance, how about back flushing?
Aparently no, on the perforated pipe, but backflushing is accomplished to each of the filtration plant parallel tanks several times a day.
6. The article implied chlorine was required because of regulations only, not necessary, is that true?
True, the output of the filtration tanks is clear.
go to Daryl's web site page 2: http://www.ccountry.net/~corchero/DarylHawkins.htm
visit Vic Corchero's Shady Cove Council web site at: http://www.ccountry.net/~corchero/whyrun.htm"
to know all about Vic, visit my 1998 political web site at: http://www.ccountry.net/~corchero/campaign.htm
Designed by, Victor Corchero , last update 9-11-00