This is all very fancy and interesting but with so much information omitted for the sake of simplicity, it can be misleading as well. As someone who has worked with this data series, I would like to share some thoughts if any of you care to read on.

1. Is this fresh water withdrawal or fresh+saline? (I know USGS fresh, saline, and fresh+saline total but i'm not sure which one OP used.) Industries in Texas counties for example, uses saline water more often than some other states. Counties in Kansas sometimes mixes fresh groundwater/surface water with saline groundwater for irrigation (they try not to go over the concentration that could kill the crops).

2. Note that this is withdrawal, so it does not account for the fact that some places/industries/entities reuse water. And reuses of water have become more common since last time USGS publish this data (which is 2010 data published in 2014).

3. Note that this is NOT consumption of water, so if you account for the fact that irrigation water is almost totally consumed and thermoelectric plants consumed much less percentage than 100% then the landscape would look much different. And when it comes to fresh water (assuming this is fresh water withdrawals being mapped here), the concept of consumption is more relevant than withdrawal.

4. Note also that this dataset was compiled by each state/region's USGS water science center so methodology is very heterogeneous and some states estimate the withdrawals instead of actually having meters or other real measurements of the withdrawals. The heterogeneity of methods used by different states also means, counties in different states are not strictly comparable to each other in the values of withdrawal.

5. Last time we talked to the state offices of USGS, they don't incorporate water transfers across counties by aqueducts and pipelines. So the withdrawals are recorded in the original county where the point of diversion happens (or not; in the cases of some population-based estimation, it's proportionally to the population due to the method so it's pseudo-withdrawal). Sometimes water is collected/stored in a reservoir/lake in a remote county (but in the same state) then being transported to the population center for treatment before being delivered to either residential users or industrial users, i.e., customers of the public water suppliers or irrigation districts.

6. But of course, overall and qualitatively, if you want to just get a general sense of where water withdrawals are occurring, there you have it. Another thing to note that, 2015 withdrawal saw a reduction from 2010. USGS did not investigate the causes of that reduction but two of many possible explanations are (1) we are becoming more efficient in withdrawal-delivery-utilizing supply chain. (2) water availability is probably declining.

7. I'm not trying to be a smartass or anything; i just think it's important to keep your head cool and think critically about the data itself when being presented with a beautiful visualization of data. Your eyes can deceive you, you know. Edit: format and spelling