Laserfiche WebLink
Because the San Joaquin County Environmental Health Department has requested that <br /> local and recent data be utilized wherever possible, the concentration of the Lodi <br /> rainwater been selected for use in the nitrate loading calculation. <br /> Quantity and Quality of Domestic Wastewater <br /> The proposed parcel division includes a 2.11-acre (gross) homesite parcel and a 46.01- <br /> acre designated remainder. The designated remainder will be unbuildable in the future; <br /> consequently, nitrate loading has not been calculated for this parcel. <br /> According to Mrs. Galli, the existing house on the homesite parcel has five bedrooms; <br /> the attached garage with apartment has two bedrooms. Mrs. Galli has no plans for any <br /> further construction on the homesite parcel. <br /> Crites and Tchobanoglous (1998) list a typical flow rate of 50 to 70 gallons per person <br /> per day for an individual residence. In the past, San Joaquin County Environmental <br /> Health Department has requested that the flow rate be calculated as 140 gallons per <br /> bedroom per day to reflect maximum usage. On March 4, 2020, however, Michael Kith, <br /> Lead Registered Environmental Health Specialist at the San Joaquin County <br /> Environmental Health Department, stated that he has conferred with Norm Hantzsche <br /> (author of the 1992 paper discussed previously), and they have arrived at a new <br /> method to determine flow from residential sources. He indicated that wastewater flow <br /> from a single-family residence should be calculated as 100 gallons per day (gpd) for the <br /> first bedroom and 50 gpd for each additional bedroom; additional residences should be <br /> calculated in the same manner (personal communication, March 4, 2020). <br /> The main house has five bedrooms, which results in a flow value of 300 gpd using the <br /> new method. The garage apartment has two bedrooms, which results in a flow value of <br /> 150 gpd using the new method. The maximum daily flow for the homesite parcel is thus <br /> estimated to be 450 gpd. <br /> A typical residential concentration of 35 mg/L of nitrate as N was selected for the <br /> theoretical residences (Crites and Tchobanoglous, 1998). <br /> The estimated flow values discussed here should not be used for the design and sizing <br /> of the septic system. The design and sizing of the septic system should utilize the San <br /> Joaquin County Environmental Health Department On-Site Wastewater Treatment <br /> Systems Standards which incorporate peak and surge flow factors. The estimates used <br /> in the On-Site Wastewater Treatment Systems Standards may be greater than those <br /> discussed here. <br /> LOGE 20-12 Page 12 <br />