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e • <br /> Typically, a two-bedroom residence indicates a daily design flow of 240 gpd, based on a <br /> rate of 120 gpd per bedroom. Implicit in this typical rate is an assumption of normal <br /> water usage from household cooking, dishwashing, clothes washing, toileting, and similar <br /> activities. Using a design flow rate of 2 for the proposed cottage is therefore <br /> expected to be a conservative assumption. <br /> Analysis Summary <br /> The basic analytical procedure used in this report is as follows: <br /> 1. Collect daily pump data during a representative sample of weeks and estimate <br /> daily pumping volumes; <br /> 2. Focus on the summer camping weeks that include both resident camping and day <br /> camping as the data set for detailed analysis; <br /> 3. For any short periods having non-continuous daily readings, use the best available <br /> information to distribute daily volumes over the period (typically weekends); <br /> 4. Identify the top ten percent of daily usage values from the resulting data set, and <br /> average them; <br /> 5. Accept this average daily value as an estimate of"existing demand"on the LPP <br /> system; <br /> 6. Add the daily design flow volume from the proposed cottage to the calculated <br /> existing demand; and <br /> 7. Assess the impact of the cottage addition on the LPP system. <br /> Data Collection <br /> The volume of daily wastewater generation during the study period has been estimated by <br /> approximating the volume of effluent pumped from the central pumping station to the <br /> sand filter on a daily basis. Each of the duplex pumps is configured with an elapsed time <br /> meter that measures pumping time in cumulative hours. Daily readings were generally <br /> recorded by camp staff for each pump during the mid-afternoon of each day. These data <br /> are presented in Exhibit #1. The records indicate that measurements were not recorded <br /> some days, and the times of day for the readings were not strictly consistent. <br /> The rate of pumping was estimated from a draw-down test conducted by camp staff. <br /> During this test each pump operated independently for one-half how(total of one hour <br /> pumping time),producing a total water level drawdown of 29.5 inches inside the pump <br /> tank. The system operator provided the tank volume ­44.8 s per vertical inch. The <br /> pumping rate was therefore calculated as 1321.6 gallons per hour, or approximately 22 <br /> gallons per minute. <br /> The daily observations of pumping time and the measured pumping rate were used to <br /> calculate the estimated volume pumped during each day. For each day, the pumped <br /> volume is assumed to represent the actual volume of wastewater generated during the <br /> day. This assumption is not entirely satisfying,but is a necessary one considering <br /> practical limitations. Irregularities that may be introduced by this assumption will tend to <br /> 3 <br /> 290 <br />