A couple things to point out!
For complete instructions on making a ham from scratch (raw hog leg) please see my post "From Hog Leg to Easter Ham!" :
http://www.smokingmeatforums.com/t/89979/from-hog-leg-to-easter-ham - explains the whole process.
For a double-smoked ham, check around for an "uncooked" or "partially cooked" ham, it would indicate it on the label. It still has to be completely cooked to 150° - 165°; the manufacturer only cooked it to it's partially cooked minimum standard of 135°, still too raw to eat outright but cooked enough to destroy pathogens.
The term "water added" is basically misleading; it brings visions of packers intentionally pumping water into the ham to increase it's weight dishonestly.
When a fresh hog leg is processed, because of the size of the muscles, to get the brine inside before the meat spoils, you must "pump" the ham with brine or it will sour; in other words inject the brine into the muscles so it will cure from the inside-out as well as from the outside-in. You are adding a liquid brine to the meat. The average pump ratio is about 10%; that's about all it can hold. On a 14 lb ham, you will put about 23 oz of brine into the ham, or about 10% (14 lbs x 16 oz = 224 oz, ÷ 10 = 22.4 oz). Now, during the cooking and smoking process, if you do not cook out at least 5% of that moisture, your ham will be labeled 5% or 10% 'water-added'.
Then, there is higher % water-added ham product, usually in the deli-ham line, called, "XX% ham and water product", the XX's representing the weight increase, usually 20% to 40%. This is accomplished by introducing phosphates and other chemicals into the product to make it intentionally absorb more water and increase profits. And, you get what you pay for; ham-and-water product is just that, mushy! But, cheaper; I've bought it before. You just don't want to wait too long before lunch, or you'll have to wring out your sandwich before you can eat it, lol!