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HomeMy WebLinkAbout12/01/2009, B8 - 2009-10 CITYWIDE WINTER WEATHER PREPARATION 1 council �z -09 j agenda Rpm �N.,b. � CITY OF SAN LUIS OBISPO FROM: Jay D. Walter, Director of Public Works Shelly Stanwyck, Assistant City Manager Prepared By: Barbara Lynch, City Engineer, Neil Havlik, Natural Resource Manager, Bud Nance, Wastewater Collections Supervisor SUBJECT: 2009-10 CITYWIDE WINTER WEATHER PREPARATION RECOMMENDATION Receive and file a report on the City's 2009-10 winter weather preparations. DISCUSSION Background Each year, to prepare the City creeks and storm drains for winter, City staff completes a variety of activities. By preparing for wet weather the risk of flooding in the community is reduced. The work is carried out by City Administration's Natural Resources Program, Public Works, and Utilities department staff, the California Conservation Corps, and the occasional herd of goats or sheep. Throughout the year staff thins vegetation, removes blockages, responds to community identified concerns, monitors various locations, and completes CIP projects improving flood protection. For the second.year in a row, Utilities Department staff members have augmented previous efforts through the implementation of the new and expanded storm drain cleaning operations made possible by the approval of Measure Y. It is important to note that even with all of the preparation work that is done in the Fall of each year, there are some fundamental creek capacity issues in the City. Due to these issues, flooding cannot entirely be prevented in case of a major storm. San Luis Obispo Creek as it approaches the Downtown has the approximate capacity to convey a 17-year storm event. Capacity downstream is even less, and through the Mid-Higuera reach, it is closer to a 10-year storm event. This illustrates that storm events and their associated rainfall amounts may result in flooding, even though City staff has continued winter preparation activities and completed CIP projects in advance. Last year, staff prepared its first Winter Weather Preparation report, and based on the response to that presentation, has prepared this update. 2009-10 Drainage System Winterization 1. Rock Guards. Throughout the City there are about 15 rock guards. These "pipe grate" structures are typically placed near the entrance of a culvert that accepts drainage from the steeply sloped hills around town. Their purpose is to prevent large material and debris (rocks, branches, etc.) from entering the culvert, becoming lodged in place, and creating a storm water back-up that cannot be easily removed. The Street Maintenance staff checked and cleared all 3 8' l 2009-10 Winter Weather Preparation Page 2 rock guards prior to the October 13-14 storm and rechecked them all after the storm, which dropped 7 inches of rain. -� •alb Ty� _ 'w .a -sif 4 a. y Y s i X� 1 The Street Maintenance staff has also checked all the "hot spots" or historically troublesome drain inlets and culverts to make sure they are clear of debris. They have been working closely with Wastewater Collection staff in pulling and/or replacing stuck drain inlets to gain access to vacuum the inlets. Street Maintenance staff has worked closely with staff from the City's Natural Resource program and the California Conservation Corps (CCC) in providing drop boxes for creek debris as it is removed from the channels. 2. Creek Work. Creek work this year has turned out to be a little different than anticipated due to the unusual strength of the storm in mid-October. Staff had been working with CCC crews on normal thinning of willows, removal of debris and dead material, and clearing of some blocked small drainages. Staff also utilized the goats in two areas to clear the non-native cape ivy (a favored browse item for the goats) and clear the sites for further clean-up. This work was essentially complete by about October 10. However, following the storm of October 13-14, staff began getting a lot of calls regarding toppled trees, major limb breakage, and other issues. In addition, staff noted that some areas that had just been cleared were full of debris again. This was especially evident along the Bob Jones Trail near the Water Reclamation Facility. Last year there had been no storms of sufficient force to really move forest litter, etc, and thus the intensity of the October storm caused the movement of much more than would be expected of an early season storm. As a result, CCC crews were called back to re-clear the floodway at the Water Reclamation Facility and clear and remove a number of fallen trees and limbs in various places around the City. Conditions were (and are)particularly bad at the Prefumo Arm of Laguna Lake, and staff was forced to undertake a triage system by re-clearing the creek itself and moving material to where it can lodge against standing trees in case of a major flood event. This is -aa- �,, 2009-10 Winter Weather Preparation Page 3 prelude to a major anticipated undertaking next summer in that location to address the increasing problem of tree falls and major limb breakage. Staff is pursuing available grant funding to fund this work. The rule of thumb in the City's stormwater management work along the creeks is: don't lose shade over the water, and use floodways whenever possible. Hence the strong efforts at the major floodway at the Water Reclamation Facility, which only carries water during storm events and allows the City to keep clearing activities in San Luis Obispo Creek itself at that location, to a minimum. Staff carefully considers the effect of pruning and removal along the active waterways with an eye toward keeping as much shade over the creek as possible consistent with the need for maintaining flow capacity. It is a constant balancing act. 3. Multi Agency, Multi-Department Efforts to Minimize the Impacts of Homeless Encampments on the Creeks. City departments, including Administration, Parks and Recreation, Public Works, and Police have been collaborating with other agencies at the County and State level, as well as private landowners, to try to address the issue of homeless camps in creek areas and the problems that have attended the occurrence of such camps. These problems include but are not limited to accumulations of garbage and litter, damage to riparian vegetation, and lack of sanitation. Several areas have been cleared of camps and the areas cleaned up, but as the Council is aware this issue does not simply go away; instead it is transferred to other sites either in town or just outside of it. Nevertheless, staff is working with other agencies and the City Attorney's office to develop an ordinance that will strengthen the City's abilities to control the abuses that accompany camps along the City's waterways. It is expected that this ordinance will be ready to be reviewed by the City Council in the near future. 4. Stormdrain Cleaning. As part of the City's enhanced Storm Water program, scheduled maintenance cleaning of the storm drain system is routinely being done. This work ensures the drainage inlets are not plugged, which would prevent water from entering the system, reduces flooding potential and debris from entering into the creeks and storm drain infrastructure system. Wastewater Collection staff has developed a comprehensive maintenance program utilizing the Hansen Infrastructure Management System (IMS) data base. Staff has continued to work with the Public Works Geographical Information System (GIS) department to develop and update the storm drain maps. The Hansen data base integrates with the GIS system to assist staff in the field to electronically locate and manage storm drain assets and IMS information. For efficiency and historical information staff accesses maintenance records and GIS information via a mobile wireless laptop computer to create and complete work order information. Staff has organized and developed 9 Area cleaning basins throughout the City to coincide with the Pavement Management Plan areas. The Downtown basin is scheduled and cleaned yearly prior to the rainy season. Since the program started, staff has completed two catch basin cleaning cycles covering the entire City, cleaning and inspecting approximately 2,220 catch basins. The program has removed 212 tons of debris. In mid-October, the City received a significant storm. Total rainfall reported was between 6-7 inches. Catch basin problem areas normally requiring emergency response or the placement of "flooded"signs, needed no attention. Stormwater flowed without interruption and there were no P)t-3 2009-10 Winter Weather Preparation Page 4 significant problems reported or customer complaints. This storm, by and large, affected trees due to the time of year and high winds. -< -Nv- S. Downtown Flood Protection. Each year staff reminds businesses, through the Downtown Association newsletter, of the need to prepare for winter weather. Specifically they are reminded to clear roof gutters and to locate flood gates so they are ready and accessible. Much of the Downtown core is in the 100-year flood plain and as such, major remodeling and new construction is required to raise the floor elevation or protect the property with flood gates. Flood gates typically consist of boards of some sort which are fixed in front of the doors to reduce flood water intrusion. In the event of high water, the businesses or property owners are responsible to install these gates to protect their property. For liability reasons, the City does not tell businesses when they need to do this; however, during severe weather, the City does release ongoing updates on the status of the flooding event and the potential for rising waters. City staff monitors weather reports, County stream gauges at certain creek locations, and has observers in the field that report on the situation to the Department Operations Center at the City Corp Yard. Capital Improvement Projects Currently active in design are plans to complete replacement of a failed pipe system along Bullock Lane and So. Higuera Street below Elks Lane, as well as a damaged box culvert crossing S. Higuera Street north of Elks Lane. The projects are anticipated to occur in the spring and summer of 2010. Regulatory permitting is underway for silt removal projects in the Prefumo Creek Arm of Laguna Lake, in San Luis Creek above Los Osos Valley Road and adjacent to the Water Reclamation Facility, in Sydney Creek at the railroad (near Sinsheimer Park), and under the Tank Farm Road bridge near Hollyhock. Actual removal is anticipated to occur in the summer 2010. Work on silt removal downstream of the outlet from Laguna Lake is scheduled to occur during summer 2011. i 2009-10 Winter Weather Preparation Page 5 Through an effort of the Zone 9 Flood Control and Water Conservation District, technical studies for environmental work are beginning for the Mid-Higuera creek widening. The County is starting preparation of technical studies that will be used for development of the project's environmental report. The technical studies are anticipated to be complete by the fall of 2010. The project currently being studied is one that involves widening or overflow channels only on those properties owned by the City. City Staff is currently investigating the viability of a lot line adjustment with one adjacent property owner that would allow improved flow characteristics for this project. Project funding has solely been provided by Zone 9 to this point. In September construction was completed replacing 90 feet of collapsed storm drain pipe at California Blvd and Stafford Street. Final work is being done on the replacement of 70 feet of failed storm drain pipe at the intersection of Stafford and Kentucky streets. In Almond Street 500 feet of failed pipeline was replaced in January of this year, and another 340 feet of failed pipe was replaced this month in Mission Lane. Miscellaneous Preparations Sand has been delivered to the Corporation Yard, Laguna Lake Golf Course, Sinsheimer Park and Santa Rosa Park and is available to the public in the event they experience localized flooding. Community Service workers have been used to fill and palletized sandbags for emergency response and all chainsaws have been checked and repaired. Although the Winter Weather web page is available all year, staff places a reminder about the web site and the need to prepare on Channel 20 during the rainy season. Radios have been delivered to response crews in the event we lose cell phone contact. The Winter Weather preparedness web site covers a variety of topics including how to be safe while traveling during storms, what to do if downed power lines are observed, how to protect your home from flooding, and about flood insurance. City staff also hosts a booth at Farmer's Market during December, distributing winter weather information and answering questions from visitors. FISCAL IMPACT The County Board of Supervisors has authorized approximately $100,000 of funding, through the Zone 9 Flood Control and Water Conservation District, for natural channel clearing and public outreach. While this funding has a long tradition of being available to the City for this type of work, it is discretionary on the part of the County Board of Supervisors to provide it. With the exception of silt removal projects, the remainder of the Capital Improvement projects are funded with General Fund. ATTACHMENT Best Management Practices Flood Protection Fact Sheet Various other winter preparation brochures are in the Council Reading File 1 City of San Lair Obispo Pu&., Works Department ATTACH ME�i' StornrwaterMauagement Program is 919 Palin Street;San Luis Obispo, CA 93401 (805).781-7530 BEST MANAGEMENT PRACTICES FLOOD PROTECTIONFACT SHEET FLOOD FACTS • City of San Luis Obispo Flood-Plain: The City of San Luis Obispo's flood-plain consist of four major streams and numerous minor waterways which can cause flooding. The four major streams are: San Luis Obispo Creek,Sterner Creels,Old Garden Creek and Prefumo Creek. • Flood Zone Maps: To find out if your property might be located within a flood zone, feel free to give us a call for more specific information at(805) 781-7201 or visit www.getreadyslo.com. ■ Flood Prediction: Flooding can occur with little or no warning! ■ Flood Warnings: In coordination with the local Office of Emergency Services, the County of San Luis Obispo and the National Weather Service issue emergency flood warnings through the local radio and television stations. These warnings are typified with "for the next 60 seconds, this station will conduct a test of the Emergency Broadcast System...". During severe weather, the City will provide information on Government Channel 20. ■ Flood Duration: Flooding can last from 30 minutes to several hours which really is not that long. However,the effects of a flood can last a long time! ■ FLOOD SAFETY: Traveling During Flood Warnings: Best advice;don't go ou ,unless you must. Be extra aware of your surroundings and possible hazards. Pay special attention to road conditions. Note the amount of water flowing in or.across flooded streets and under or over bridges. Do not attempt to cross flooded streets. Avoid problem areas and always plan an alternate route,if possible, before you leave your home or business. Make sure to tell someone where you are going and when you should reach your destination. o Precaution: Remember- flood water currents can be very deceptive - six inches of moving water can T cause you to lose your footing. o Do not walk through flowing watee. Drowning is the number one cause of flood deaths, mostly during flash floods. Currents can be deceptive;six inches of moving water can cause,you to lose your footing. o Car Safety: More people drown in their cars than anywhere else. Only two feet of water can sweep away an automobile. The moral, do not drive around road barricades; the road or bridge may be washed out or unstable, or may be subject to swift currents. o , Downed Power Lines: Stay- away! We repeat, stay away from power and electrical. wires. The second leading cause of death in floods is electrocution. Electrical current can travel through water. Report any downed power lines to Pacific Gas&Electric Company at(800) 743-5000 or the City Police Department at(805) 781-7317. o Site Seeing& Rushing Water. During heavy storms,many people want to park their car or stand on bridges over creeks to watch the swift-moving water. However,in a manner of seconds, large floating objects,like a fallen tree, can jam under the bridge, forcing the rushing water over the top of the bridge and possibly sweeping you, your car and anything else into the creek. Stay away from creeks and bridges during a storm event. o For more flood facts visit our websites at: or www.getreadyslo.com or http://wurw.slocity.org/public\vorks/stormwater/stormwater°/`20work°/o20in%20progress`/`201°o20a. ate. Best 211niragement Practices Fact Sheet for Flood Prenerttiw(Rei).121200S) Page1 of�2 'Q r6V — (,V City oJSan Luis Obispo Pubes:Works Departmentmerogram 919 Palm Street;San Lds Obispo, CA 93401 ATTACHMENT Stosmmater Man(80age5);.nt781P-7530 FLOOD PROTECTION: Flood Insurance: Anyone can carry flood insurance; it is not limited to those properties in designated flood zones. If you don't have flood insurance, talk to your insurance agent. Homeowner's insurance policies do not cover damage from floods. However, because the City of San Luis Obispo participates in the National Flood Insurance Program, you can purchase a separate flood insurance policy. This insurance is backed by the federal government and is available to everyone,even if your property has been flooded. ■ Property Protection: There are numerous things you can do to protect your property and reduce the risk of flooding and/or minimize potential flood damage. There are preventative measures and reactionary measures. Preventative measures and reactionary measures are both outlined in the City of San Luis Obispo's Best Management Practices for Flood Protection brochure and in more detail in the City's Best Management Practices for Flood Protection guide. Both are available on-line at www.sloci!y.org. Additional resources are available at http://getreadilslo.com or just call us at (805) 781-Rain for additional assistance. • Creek-side Living: 'If you live nest to a creek or drainage way, find out its past history before the rainy season hits: Then,during heavy storms, keep a watch on the rising water and report any potential problems you see to the staff at the City Yard at(805) 781-7220. • General Flood Prevention Measures: Clean out debris from the drainage ways around your property. Debris, vegetation or anything blocking the drainage way can easily be removed during the dry season and can dramatically reduce flooding problems during winter storms. o The City inspects the major creeks and many of the minor waterways each year before the rainy season. Reporting fallen trees or broken drains and pipes is a great help and allows us to make repairs before the rains come down. And if you notice that one of the street drainage systems is blocked,please call us and let us know so that we can clean up the mess. o For more flood prevention measures and tips visit our website at: http://NNrNclv.slociti-.org/pui)licworla/'stormwater/stormwater%20work%20in%20progress%201 20a.a�jp or visit w-w%v.fema.Vov or visit http://getreadvslo.com. FLOOD ZONES AND DEVELOPMENT ISSUES! ■ Building in a Flood Zone: Just because you own property in a flood zone does not mean that you can't develop it. Usually you can, but you will encounter stricter flood zone specific development conditions. Construction cost will usually be higher,as well as,design costs. All new buildings must be raised above the established flood levels (commercial buildings may incorporate flood proofing, if in the opinion of the City, elevating the building is not feasible. • Remodeling in a Flood Zone: If you own a building in a flood zone and decide to remodel it or add on, you may be required to bring the building into compliance with the current flood regulations. This occurs when the total value of your remodel or addition (during any five-year period) equals or exceeds fifty percent (50%) of the market value of the building before the new improvements are done. The market value does not include the value of the land. MORE QUESTIONS? • General Information: The following services are available by calling(805) 781-7220: o Sandbag fill material and creek and storm drain clearing. o For additional information on local development requirements, flood insurance rate map (FIRM) interpretations, flood elevation data and flood insurance requirements call the Public Works Development Review Sections at(805) 781-7015. o So call us at (805) 781-RAIN or check us out on the Web at We are ready for anything and so can you. Bert illanagemew Practices Fart Sheet Jor Flood Prevention(Rev.121200S) Page 2 of 2