NOAA’s Climate Prediction Center issued its latest ENSO update on September 10, 2026. Its summary is short: El Nino is strengthening, with a greater than 90 percent chance of a very strong event during the fall and winter of 2026-27.
That is worth knowing, and it is worth being precise about what it means. El Nino is a climate pattern, not a storm on a calendar. A strong event raises the odds of a wetter than usual winter in Southern California. It does not promise San Diego a particular amount of rain, and NOAA’s own language is that with an event of this size the chances of El Nino-type impacts are larger, though not guaranteed.
So this is not a warning. It is a reason to do the maintenance you were probably going to put off. The useful thing about a wet winter is that it does not create drain problems. It finds the ones that were already there.
Why rain shows up in drains that seemed fine
A sewer line that is two thirds blocked works perfectly well in August. Water goes down, nothing backs up, and there is no reason to think about it.
Then the ground saturates. Groundwater finds its way into cracked pipe and old joints, which is called infiltration, and the line that had a third of its capacity left now has less. Add the ordinary load of a household and that is when the shower starts standing and the floor drain gurgles.
Two things cause most of it in San Diego County, and they are the same two things whether the year is wet or dry. Tree roots find the moisture and the small openings in an older line and grow into it. Grease and buildup narrow the line from the inside, particularly in kitchen and restaurant drains. Rain does not cause either one. It just removes the margin you had.
Older neighbourhoods feel it first. La Mesa, Lemon Grove and parts of El Cajon have mature street trees over clay and cast iron laterals. Out in Ramona and the backcountry, the runs from the house to the connection are longer, which means more pipe for a root to find.
What you can check yourself, before it rains
None of this needs a plumber. Most of it takes an afternoon.
Clear what you can reach. Gutters, downspouts, yard and area drains, and the grates over them. The City of San Diego’s storm preparedness guidance asks residents to sweep up trash, sediment and debris so it does not enter and block the stormwater system, and that starts on your own property. While you are out there, check that downspouts actually discharge away from the foundation rather than into a planter beside it.
Watch how your drains behave right now. This is the most useful thing on the list and it costs nothing. Run the tub, the kitchen sink and a washing machine cycle, and pay attention. A drain that empties slowly in dry weather is the one that backs up in wet weather. So is a toilet that bubbles when the washing machine drains, which usually means the problem is in the main line rather than in one fixture.
Find two things and write them down. Your main water shutoff, and your sewer cleanout. The shutoff is usually at the meter or where the supply enters the house. The cleanout is a capped pipe, often near the foundation or in the front yard. Knowing where both are in daylight is worth a great deal at ten at night with water on the floor.
Move what water can ruin. Anything stored on a garage or basement floor near a floor drain. Cardboard, tools, paperwork, anything with a motor in it.
Leave the rest alone. Do not pour chemical drain cleaner into a line that is already slow. It sits against the blockage, it does not clear a root mass or a grease layer, and on older pipe it does damage that a plumber then has to work around.
Signs that justify a professional look before the rain
Not every house needs an inspection. These are the conditions that actually warrant one.
- More than one fixture draining slowly at the same time, which points to the main line
rather than to a single trap - A drain you have cleared before that keeps coming back, particularly on the same
schedule - Sewer odour inside the house or around the yard
- Soggy ground, unusually green patches or a dip in the lawn over the line’s route
- Water rising in one fixture when you run another, a shower filling when the toilet
flushes - A property with mature trees over a clay or cast iron lateral, which in much of
San Diego County means a house built before the 1970s - A restaurant or multi-unit building where a backup means closing
If none of these describe your property, the honest answer is that you do not need to do anything but the checklist above. If several do, the useful move is to find out what is actually in the line before the weather makes the decision for you. Our sewer line warning signs guide goes through what each of these symptoms usually turns out to be.
When an inspection or a jetting is worth it
A sewer camera inspection answers one question: what is the condition of this line, right now. It shows roots, cracks, corrosion, bellies and offsets, and it is the difference between guessing and knowing. It earns its place when a line has a history, when a house is old enough that nobody knows what the lateral is made of, or when a repair is being quoted and you want to see what you are paying for. It is not something every property needs every year.
If the camera shows roots or heavy buildup rather than a broken pipe, clearing the line properly is the fix, and that is a drain cleaning job. Cabling handles a lot of it. Heavier root mass and grease usually need more. What a line does not need is the most aggressive option applied on principle.
Your drain, the city’s drain, and who to call
This is the part that costs people money, so it is worth being clear.
The storm drain in the street is public. The City of San Diego’s Storm Water Department is responsible for inspection, maintenance and repair of the storm drain system in the public right of way and in drainage easements. If one is blocked or flooding, the City asks residents to report it through its Get It Done app, and it lists 619-527-7500 for non-emergency flooding reports. In the unincorporated county, drainage problems go to County Public Works Field Operations at 619-443-1260 on weekdays. Other cities in the county run their own systems, so check with yours.
Your sewer lateral is private. The City’s own guidance is unambiguous: the entire length of the sewer lateral, from your building to its point of connection with the City sewer main under the street, is your private property, and keeping it clear of roots, grease and debris is your responsibility. That is true even for the portion running under the street.
E-Drains works on private property. We do not service, clear or repair city-owned storm drains or sewer mains. If your line backs up, that is us. If the street is flooding, that is your city or the county.
Routine preparation versus an actual emergency
Everything above is preparation. You do it on a Saturday, on your own schedule, and nothing is on fire.
These are different, and they are the point at which waiting costs more than calling:
- Sewage backing up into a tub, shower or floor drain
- Every drain in the building stopped at once
- Water coming up through a slab or standing where it has never stood
- A backup in a commercial kitchen or a multi-unit building
If that is what you are looking at, shut off the water if a supply line is involved, keep people away from standing water near electrical outlets, and call. A person answers our phone 24 hours a day, seven days a week, and
emergency drain service is what we do. If the water has already got into the building, we also handle
flood and water damage cleanup, including the documentation your insurer will ask for.
For what to do in the minutes before anyone arrives, we have a step-by-step guide worth reading now rather than then.
A reasonable plan for this fall
Do the checklist yourself in the next few weeks. Pay attention to how your drains behave while the weather is still dry, because that is the cheapest diagnostic there is. If something on the warning signs list describes your property, get the line looked at while scheduling is easy rather than during the first week of steady rain, when it is not.
If you want a straight answer about what your line is doing, call us. We serve La Mesa, El Cajon, Santee, Ramona, Poway and across San Diego County, we give you the price before the work starts, and a camera inspection is included with our drain cleaning service so you can see what we are seeing.