Mystery Water

Was in the basement this morning after the rain and had the usual somwhat expected puddling. Just got home after a full day out and the basement floor has much more water than earlier. Any clues?

The last time our basement flooded, it was a leak from the hot water heater.  Hope that yours is easily solved.

If not plumbing leak, like what EBennet suggested: 

Though most of rain from storm fell by daybreak, snowmelt continued during day. I do realize much of snow was already melted by daybreak in many locales. But it could explain it, as ground seems saturated.

yeah, I was just thinking it was groundwater.

Is the solution then only a pump or French drain? All my downspouts and the dirt are graded away from my house.

Th Google has information on do-it-yourself waterproofing. 

If you decide to go professional, get a quote from Gold Medal. When I was getting quotes, they were the most thorough and cheapest. I didn't do the waterproofing. It was an inherited house and we sold the house instead. 

Regarding the professionals, the guy comes to your house. Get a quote and tell him you will think on it. You usually get a second, lower quote if you "sign today."

If you don't have a history of any ground water in the basement, it could be a plumbing issue.  If you already had groundwater in the basement and amount of water in the basement rose during the day, it is almost certainly more ground water.  The underground streams through much of our area almost certainly rose with the amount of water that fell during the day compounded by the significant amount of snow melt which would have not been dealt with by your leader and gutter system.  In this case, you would need to determine where/how water is getting into the basement and come up with a plan for waterproofing if the water in the basement issue proves a problem.  

rhw said:

Is the solution then only a pump or French drain? All my downspouts and the dirt are graded away from my house.

 Yes. It’s coming up from below. Snow melting in a rain storm will cause it. Since it’s not something that happens often I would just install a sump pump. Keeps the water from coming up through the floor.

Is a sump pump installation a diy? Or how much to get put in?

My own sump pump involved the creation of a rather large (maybe 18” diameter or so) open hole/drain in a concrete floor. Definitely no one’s idea of DIY, I’m guessing. My parents - despite extensive attempts at remediation - have had basement water for decades - often worse on day two or three after rain. An awful lot of homes in this area were built on what today would be declared unbuildable wetlands, I think. 

rhw said:

Is a sump pump installation a diy? Or how much to get put in?

 I did my own. Have to make a hole about 24 inches in diameter, and about 24 inches deep. I bough the plastic catch basin from Home Depot along with the sump pump. I took out quite a bit of dirt, which was wet. Put some crushed stone (3/4 inch crushed stone ) on the bottom of the hole. Then place the bin/basin on top of the crushed stone. I also added about two more bags of crushed stone around the outside of the bin. 
must have an electrical outlet close by. And I installed a 11/2 pvc pipe through the basement wall to the outside. Make sure the outflow is far away from the house foundation. I bought everything at Home Depot.

I’m pretty handy. But for some people it’s just not something they would want to undertake. A weekend project. But I saved a lot of money doing it myself.

Yeah, I did my own pump too, back in the day. The hardest part is cracking through the concrete floor. It's doable, but definitely a more advanced DIY.