Laserfiche WebLink
4.1s cel' i};�: aitCr rC;U( }l LltticjUm:n Creek branches. Tne north brunch }�csd:Ld <br /> h <br /> about 1/2 mile north of the site and the south branch crosses th` >rit as <br /> previously discussed. <br /> a <br /> No record of the flood frequency for which .the Littlejohn Creek <br /> project was designed was found in project manuals provided by the Army Corps <br /> of Engineers or determined from discussion with staff of the Corps Levee-and <br /> Channel Division. San Joaquin County Flood Control Division Staff estimate <br /> that the channel was designed for a 50-year flood frequency. The peak flows <br /> in Littlejohn Creek and in Duck Creek at Farmington between 1903 and 1964 occurred <br /> in 1958 . County records show that in the Winter of 1958, a peak flow of <br /> 3500 CFS was diverted from Duck Creek to Littlejohn Creek. This flow is <br /> 175% of the 2000 CFS combinecL design capacity of both North and South Littlejohn <br /> Creek and resulted in overtopping of the channel east of Jack Tone Road. <br /> However, County flood record maps indicate that no flooding of the proposed <br /> disposal site occurred. While flooding of the site by waters of Littlejohn <br /> Creek does not appear to occur due to overtopping of the channel in upstream <br /> areas, there is a potential ,for temporary ponding of local runoff on the site <br /> at high creek stages. Such shallow ponding of local runoff on the site <br /> occurred during the Winter of 1955• <br /> All of the above flood control facilities are operated and maintained <br /> by the County of San Joaquin Department of Public. Works. The channels are <br /> dredged periodically to maintain design capacity. Dredging spoils are cast <br /> alongside the creek channel and are graded to form a levee paralleling the <br /> channel . Typical sections of the levee and channel are shown on Plate <br /> Farmington Reservoir Regulation Manual (Rev. Octover 1967) , Army Corps of <br /> Engineers. <br />