top of page

Preparing for El Nino

Updated: Sep 14, 2020

The El Nino is a tropical weather pattern with consequences in the northern hemisphere. An El Nino (or more specifically the El Nino Southern Oscillation, or ENSO) weather pattern is characterized by the above average warming of the surface temperature of the ocean waters in the eastern portion of the Pacific Ocean. This warming pattern starting from the equator results in extreme weather conditions such as mild winters in the eastern and northern portions of North America and heavy rains causing localized flooding in the eastern Pacific Ocean regions.  While it has not been determined that it will strike Northern California, forecasters generally agree that Southern California will receive large amounts of rainwater.  While we are all looking forward to receiving measurable amounts of rain especially if it ends up in our water table, large amounts of rain over a small period of time is a also a great problem.  Here’s the kicker: there is an 80% chance that the El Nino could arrive between October and November.  I hate to break it to you, but that is a mere ten to twelve weeks away.

The time to prepare is now and even if you already have emergency preparedness plans, it might be good time to dust them off and review the procedures with staff because if the El Nino condition shows up as expected and causes heavy downpours, your agency will certainly be looked to from those requiring emergency assistance.  Here is a compilation of emergency preparedness ideas (from scattered internet sites) you might want to consider undertaking now:

  1. Structure preparation – Check the roofs, flashings, roof vents and windows of your municipal buildings for potential leaks. It may be too late to schedule a complete roof replacement but you certainly can get minor leaks or tears repaired.  The gutters and downspouts should be checked to be sure they are free from obstructions to allow rapid drainage of water accumulated on the roof, especially flat roofs. This is especially important for any municipal structures that may be designated as evacuation centers for those residents displaced by flooding or other problems.  Access to these buildings should also be checked for low laying spots or other issues.

  2. Storm water collection system – Make a concerted effort to check your local storm drainage collection system gutter inlets and storm water pipe sections for clogs or debris. If your storm drainage system is designed for a 25 year event or a 50 year event ( was designed to handle a lessor storm expected every 25 or 50 years) but a 100 year event shows up, you will probably have storm water capacity problems.  Plan for it.  If a different agency is responsible for the larger flood control basins (typically the county), contact them to see if the major washes, ditches, rivers and whatever else conveys large volumes of storm water, is as prepared as it can be for flood waters in large amounts.

  3. Emergency supplies – Check for your stock of consumable rain event emergency supplies such as empty sand bags, sand, straw diversion rolls, heavy millimeter plastic tarps other supplies that that may be in great demand during a flooding event.

  4. Utility Systems – Protect your potable water supply and distribution systems. Older water and wastewater collection systems may be subject to inflow from a raising ground water. In wastewater that could create a capacity problem at your wastewater treatment plant creating overflows.

  5. First responders – Review your emergency preparedness plans with your agency’s first-provider staff. This would include your police, fire/medic and public works maintenance staffs and perhaps even building inspectors. Be sure they have adequate and sufficient training, supplies and specialty equipment.  An example may be chainsaws if a number of trees come down.  Trees coming down could cause power outages or additional flooding if tree limbs then flow to the storm water collection system inlets.  Other necessary equipment would include reflective saw horses, detour signs, K-rail sections, and sump pumps as needed.

  6. Special Issues – Those of you that have experienced a recent fire contiguous to or in your city are certainly more aware of the potential for flooding with even a smaller storm event and you probably have K-rails available and ready to be installed on steep streets coming out of larger canyons. If your agency has a river or large stream, you might check to see if your swift water team is fully staffed and prepared.  You may even wish to prepare financially for the additional hours by approving an additional budget for overtime costs.  Beach cities can expect temporary flooding in low laying areas due to the probable storm surge and additional water flowing out of inland rivers causing a much higher tide than usual.  Areas prone to flooding will need to be warned or perhaps beach sand berms created.   Cities with hillsides need to be prepared for slides, especially after a number of rain days.

  7. Emergency shelters – The readiness of these very important facilities has been mentioned previously (i.e. roofs, supplies, access, etc.) but you may wish to touch base with the local Red Cross or similar type groups to confirm their readiness and willingness to assist the residents within your agency.

Preparation is not without substantial costs, but those costs will probably be far less than the cost of replacing or repairing damaged infrastructure that could be incurred, or your agency somehow fails to protect or serve your constituency.

4 views0 comments

Recent Posts

See All

Budgetary Pitfalls - Revisited

As most of you are neck deep in your budget, we thought we would remind you about some budgetary pitfalls that we have experienced over the years. GENERAL FUND If your city has been diligent about rai


bottom of page