When the engineers first came on the Southview property, they found a capped well and a small structure here. That well had fallen in, so they abandoned it.
Sweet, Edwards & Associates, Inc. of Kelso, WA was then hired by Davidson Industries to deal with water issues, and their report dated February 26, 1981 had this to say about it. It is presented below exactly as it was written.
SOUTHVIEW P.U.D. GROUND WATER SUPPLY
BACKGROUND SUMMARY
“The ground water investigation for Southview P.U.D. began with a geologic reconnaissance study in January of 1980. This brief ground water supply evaluation described the geology of the local area and outlined several options for ground water development.
Davidson Industries then retained Christensen Well Drilling Company to complete two wells on the property which were designated Well 1 and Well 2. Well 1 is located near the entrance of the west access road at coordinates II 15,582, E 6,105. This 6‑inch well is 405 feet deep and encountered 34 feet of sandstone overlying 370 feet of basalt with intercalated sediments. Well 2 is located 100 feet northwest of Well 1 at coordinates N 15,670, E 6,060. This well is also 405 feet deep and 95 feet of sandstone overlying interbedded basalts and sediments were encountered during drilling.
(Editors note: The drilling of Well 1 was completed on February 28, 1980, and the drilling of Well 2 was completed on Marcy 3, 1980. The depth to water in Well 1 was 73 feet, and the depth to water in Well 2 was 169 feet. My thanks to Frank Kistner for this information.)
Following completion of the wells, a pump test (24-hour drawdown, 24-hour recovery) was made for each well by Christensen Well Drilling Company. In addition, samples were obtained for water quality analysis at the end of each test. Water quality testing showed iron levels of 0.3 mg/1 and 0.7 mg/1 for Wells 1 and 2 respectively. The maximum allowable iron concentration is 0.3 mg/1. Chloride levels were 50 mg/1 and 48 mg/1 for Wells 1 and 2 respectively.
Following the 24-hour tests on Wells 1 and 2, a 45-day test was conducted in which Wells 1 and 2 were simultaneously pumped at 15 gpm and sampled periodically. The owner’s representative monitored this test, but the water table measurements were misplaced. However, Mark Christensen estimated the depths to water at the end of the test using the well discharges and projecting these onto the manufacturers pump rating curve. Based on the curve, the water levels at the end of the 45 day test were projected to be approximately 240 feet deep, which is approximately 60 feet below mean sea level. Although chloride levels remained low throughout this 45-day test, the deep pumping level of the water table caused concern from Lane County that salt‑water intrusion could occur with extended pumping.
Because of Lane County's concerns, David Pedersen and Associates contacted us to review the data obtained to date. The location of Well 3 was suggested because it would allow the use of Well 1 as an observation well, it increased the separation from the ocean shore, and increased the chance for recharge from nearby Berry Creek.
Sweet, Edwards & Associates, Inc. began an active part of the study on the last day of drilling for Well 3. At this time recommendations were made as to well depth and pump placement. Since there was an apparent potential for chloride intrusion, a 72-hour drawdown, 72-hour recovery aquifer test was designed to determine long‑term well yield and water quality in Well 3. The testing procedure included the use of Well 1 as an observation well during the aquifer test. It should be noted that the pumps were removed from Wells 1 and 2 to simplify direct water level measurements. When the pumps were removed, extensive iron slimes were found to be clogging the intake ports of the pumps. This made the drawdown projections made on the basis of the pump rating curve suspect. Based upon this new information and the performance of Wells 1 and 2 in the 24 hour pump tests, we do not believe that water table drawdown during the 45 day test dropped below mean sea level as was previously believed.
WELL 3 AQUIFER TEST
(Editors note: The drilling of Well 3 was completed on January 28, 1981. Well 3 has a total depth of 178 feet, and the depth to water in this well was 25 feet. Its yield was originally thought to be 60 gpm, but later held at a steady 33 gpm. My thanks to Frank Kistner for this information.)
The Well 3 aquifer test took place from February 2 through February 7, 1981. On February 2 static water level measurements were made in Wells 1 and 3 to determine the tidal efficiency of the aquifer. At 8:44 a.m., on February 3 the pump in Well 3 was started. Discharge was monitored continuously using an orifice bucket and held steady at 33 gpm. Water level changes in pumping Well 3 and Well 1 were made with electric well sounders. Time drawdown curves were continually updated to monitor the progress of the test.
Water quality sampling continued throughout the pumping portion of the test. Samples for iron and chloride analysis were obtained at intervals of 6.1, 25.3 and 48.8 hours as measured from the start of pumping. After 48.8 hours of pumping, a sample was obtained to test for the presence of phenols and a sample was obtained for bacteria analysis.
The Well 3 drawdown cone of depression reached the Berry Creek recharge boundary after approximately 950 minutes (15.8 hours) of pumping. After this time it can be seen that the fluctuations in the drawdown curve are solely due to ocean tidal effects on the aquifer. The aquifer response to tidal fluctuations in Well 3 can be compared to those in Well 1, which is closer to the shoreline.
Water level fluctuations in Well 1 during the testing of Well 3 are attributed to aquifer response to tidal fluctuations. There is no evidence Well 1 was affected in any way by the pumping of Well 3.
Although semi‑equilibrium in Well 3 was reached after less than 16 hours of pumping the drawdown portion of the test was continued for a total of 49.1 hours at 9:45 a.m. on February 5, 1981. At this time the pump was shut off and the recovery measurements begun. Within 17.08 hours the water level in Well 3 had recovered to within 1.08 feet of its static level. At this point (4:20 a.m., 2/6/81) it was decided to restart the pump and run a mini‑test at a higher discharge (48 gpm).
RESULTS OF WELL 3 AQUIFER TEST
The transmissivity of the basalt aquifer is 760 gpd/ft based upon the time drawdown and time recovery curves. The cone of depression never reached the observation well because of recharge by Berry Creek, therefore calculation of a storage co-efficient is not possible.
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YIELD. Well 3 was pumped to semi‑equilibrium at 33 and 45 gpm in separate tests. In these two tests the specific capacities of the well were 0.7 and 0.85 gpm/foot of drawdown, respectively. The pumping level of Well 3 at 45 gpm was 57.8 feet or approximately 30 feet above mean sea level. This high pumping level and the nearby recharge of Berry Creek indicate that sea‑water intrusion at Well 3 is not possible at this discharge. However, an air line should be set up on the final pump installation to allow a semi-annual check of the pumping level.
WATER QUALITY. Iron, chloride, phenols and bacteria levels were well within accepted levels. Iron was checked because iron concentrations requiring treatment were found in Wells 1 and 2. Chlorides were checked because of the sea water intrusion question. Phenols were checked because there is an asphalt plant upstream on Berry Creek. All indications are that the only water treatment that will be required is chlorination, which is routinely required for community ground water supply systems.
(Editors Note: Southview has not yet had to chlorinate its water due to the ‘negative’ reports we get from testing our water every three months. Currently our water is cleaner and clearer than the treated water in Florence!)
CONCLUSIONS AND RECOMMENDATIONS
1. Well 3 should be utilized as the community supply well coupled with a storage reservoir.
2. Long‑term yield of 33 gpm up to 50 gpm should not induce sea‑water intrusion at the above described pumping levels.
3. A quarterly air line check of the Well 3 pumping level should be written into the Homeowner's by‑laws. This can easily be done concurrently with chlorination and bacteria monitoring as required.
4. Place a protective barrier around Well 3, pumphouse, and chlorinator to protect against vandalism and vehicle damage.
5. Well l could be plumbed as an emergency temporary backup water supply, e.g. supplemental fire protection. An air line should be placed on Well l and monitored so that the pumping depth does not exceed 170 feet. If intended as a potable supply backup, the water from this well must be treated for iron removal in addition to chlorination.”
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Well #3, was drilled on property that was, at the time, owned by Ray and Bobbie Wells. That well is the well we get our water from today, and is located inside the Berry Creek Quarry gate, about 200 yards to the east of that location. An agreement between Mr. & Mrs. Wells and Davidson Industries allowed Davidson to drill the well, build a pump house, lay water lines, and get access, exclusively. The agreement, signed in 1982, also gave Mr. & Mrs. Wells the right to install a one-inch water tap or connection to the well, provided they didn’t draw more than five gallons of water per minute.
At some point later on, Davidson Industries bought the Berry Creek Quarry property from Mr. & Mrs. Wells, making the above mentioned agreement mute. The Southview Homeowner's Association has since bought the land our well sits on, as well as access in perpetuity. We have also been granted water rights for a fully built-out development.
State and County requirements required a water storage facility on site. This tank had to be able to store 1,000 gallons of water for every household, or 33,000 gallons. Don Davidson didn’t believe that was enough, so he simply told his designers to “double it.” That’s how we ended up with the 69,000-gallon capacity we enjoy today.
How we happened to get the water storage tank we did is another interesting story. At the time, probably in 1982 or early 1983, the only options for water storage tanks in Oregon were concrete and steel. Davidson believed that the quality of concrete on the coast was poor, and he didn’t want a steel tank due to the excessive corrosion we would have due to coastal air. The engineers knew of a company (AO Smith) in Bellevue, WA that manufactured a ‘porcelain-lined’ silo, and Don thought that would be a good idea for our water tank. At the time, Don owned a Cessna 210, so he and the two engineers flew to the location in Washington and looked their product over. He liked what he saw, and instructed his engineers to get all the information they could about the tanks, and see if they couldn’t get approval to install one in Oregon. They were successful, and ours was the first ‘porcelain-lined’ tank installed anywhere in the state of Oregon!
The base of the tank was installed first, and long curved panels of the material were stood on edge and bolted together. Once the first ‘circle’ was complete, they bolted it to the base, and went up from there. It didn’t take long to install, and in no time our tank was holding water for us!
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