Water Well Placement. How close to stream? 1

[Will007]

We are trying to set the best location for a new well. The owner wants it close to the running stream.

Any guidelines/pointers on how close to stream/river we can go?

Thanks for any help you can give.

 

[cvg]

estimate the 100-year flood level and make sure your well is not in the floodplain and that the well head is above the flood elevation. Practically speaking, it will make very little difference in the amount of water the well is able to produce whether you are 10 feet from the river or 100.

 

[civilperson]

The subgrade soils in permeable aquifers effects the gradient between the well water elevation and the stream. If in a sand/gravel system such as the Ogalala, the elevation difference is nominal or none. This is why the streams are pumped dry from field wells in Nebraska's Blue River and Platte drainage basins. For low production wells, (less than 1000 GPM), minor impact on the stream elevation will occur from the well and the impact may be lessened by horizontal distance from the stream for soils with k <or= 10<-5 cm/sec.

 

[bimr]

Check with the local authority that permits water wells.

Here are some general guidelines for locating a well.

Appropriate location of the well reduces the possibility of contamination. The ideal well location has good drainage and is higher than the surrounding ground surface. All possible sources of contamination should be at a lower elevation than the well, and the distances to those contamination sources must be in accordance with the regulatory guidelines. Surface drainage should not allow surface water to accumulate within a 15-foot radius of the well. A well must never be located closer than 10 feet to sewers, 50 feet to septic tanks, or 75 feet to sewage seepage fields.

 

[fattdad]

Most jurisdictions/health department will have requirements on well siting. You have to first comply with that. Next, theres the whole issue of your conceptual ground water model. If you are extracting water from a confined aquifer, that's a different dynamic then from a water table aquifer. For the former, surface water interaction is not often the big factor; for the latter, it can be a big factor. In water table aquifer conditions, I'd consider the well-head protection area and to what extent the flowing stream could favorably or unfavorably contribute to the water quality.

f-d

¡papá gordo ain’t no madre flaca!

 

[Hoagie]

Take a look at your draw-down envelope (cone of influence), too. Don't hesitate to talk to the driller..they know a lot.

 

[msquared48]

I believe that the EPA has guidelines here too with varying setbacks depending on the useage and flagged wetland limits. I'ved seen 200 feet or more enfoeced at times.

Mike McCann
MMC Engineering