New Search
t <br /> MEMO <br /> To: Eugene City Council <br /> From: Terry Smith, Deputy Public Works Director <br /> I~ Subject: Summary of current rainstorm <br /> Date: February 7, 1996 <br /> The City's wastewater collection system has been significantly strained by the heavy rainfall over <br /> the past 24 hours while the stormwater collection system remains in good shape with plenty of <br /> capacity. <br /> i <br /> ' Due to the heavy rains, wastewater is being allowed to bypass four major pump stations: <br /> Willakenzie, 10th and Tyler, Glenwood, and Fillmore. In all cases, the overflow is being <br /> bypassed directly to the Willamette River. The DEQ has been notified of the overflows. No <br /> public health threats are associated with the bypassing because of the tremendously high volume <br /> of water in the river. Continued bypassing will be required until there is a significant break in <br /> the rain. The current forecast is for heavy rain through Thursday. <br /> This is the first-ever bypass of the Willakenzie pump station, indicating the abnormally high <br /> level of runoff and groundwater currently present in north Eugene. Additionally, the pump <br /> station at the Eugene Airport has temporarily lost power because of flooded conditions in that <br /> vicinity. Public Works is making arrangements to bring in a portable pump to restore service to <br /> ' the airport pump station. <br /> Public Works has activated its Emergency Command Center at Public Works Maintenance, and <br /> staff is dealing with a number of minor flooding and washout problems. Maintenance Director <br /> Bob Hammitt reports that the Amazon is currently running about half full. Hammitt credits the <br /> department's aggressive maintenance program for the creek's ability to handle the heavy rain and <br /> still have available capacity. The Willematte River remains below flood stage as well. <br /> According to the National Weather Bureau, approximately 5.62 inches of rain (or an average of <br /> .23 inches per hour) fell between noon February 6 and noon February 7. This included 3.58 <br /> inches of rain recorded between midnight and 10 a.m. February 7. Total rainfall for the 36-hour <br /> period between 4 a.m. February 6 and 10 a.m. February 7 was 6.51 inches. In compazison, the <br /> annual average rainfall for the entire month of February is 5.64 inches. According to the rainfall <br /> and duration intensity curves published in the Eugene Areawide Drainage Master Plan, a 100- <br /> year storm event would be one in which 6.48 inches of rain (or an average of .27 inches per hour) <br /> fell during a 24-hour period. The most significant rain storm occurred on January 13, 1995, <br /> when a total of 4.15 inches of rain was recorded during a 24-hour period. <br /> <br /> ~r• <br /> <br />