I recently looked at a house for sale with a pond. It seemed like it would be a nice place to live. But thinking about owning the house made me consider flooding...

That flood in Mission Valley shown above happened a LONG TIME AGO,
but I was 28 at the time and remember it well.
Never rule out Nature and weather.

Anyway, back to the house with the pond (below):

I asked the realtor,
"What happens if it rains too much?"

She replied,
"You go outside, in the middle of the night
when it always rains hardest in San Diego;
you crank open the sluice gate to drain the excess 
before it floods and washes out the road 
so the other 24 households are trapped.
Then you close it before your pond runs dry."

That put an entirely different spin on living with a pond! At my advanced age, I think I would rather be here in my kitchen, front of the fire, than out in the rain. 

Besides the realtor also said,

"This is a three-level house with too many flights of stairs.
Everything is up and down, up and down. 
You don't want to buy this house if you are over 60."

I currently live near a designated "flood plain" but my house is fifty feet higher than the water level. Here's a view of running water in our back yard "creek" which reaches 6" depth at its highest.

Unlike New Orleans and other unfortunate locations, we are NOT in very much danger of flooding here. At least not to the extend that we are likely to be paddling boats through the streets. But low-lying areas can be inundated after storms, as our drainage is not so good.

See this beautiful lake? It's not a lake. It's a flooded nursery where they grow sod, near Dairy Mart Pond, where the water will eventually end up.

We have both the danger of floods from too much rain, and from too high tides. Here's a map of the areas in San Diego County that are considered in danger of potential flooding.
[Click to enlarge it]

Today I located the San Diego Flood Control District Website. They have information about recent rainfall, flooding, and videocam coverage of low-level road crossings that become unsafe after rains.

Here is a map showing rainfall in the last 24 hours along the SD River watershed.