From the Friday, July 28, 1911, Dubuque Telegraph-Herald, page 10:
EXTRA: STEAMER ST. PAUL STRIKES SNAG AND GOES TO BOTTOM
Accident Happens Near Quincy (Illinois) and Boat Sinks in Five Feet of Water  
PASSENGERS ARE ALL SAFE
Expect Craft Will Be Floated and Taken to Keokuk (Iowa) For Repairs
Quincy, Ill., July 28--The steamboat St. Paul, carrying two hundred passengers from St. Louis, Quincy and intermediate points for St. Paul, struck a snag here, sinking in five feet of water.  The passengers were not taken off.  It is expected to float the boat and proceed to Keokuk for repairs.
The St. Paul was one of the Diamond Jo Line Steamers that was acquired by the Streckfus Company in the transfer.  The craft was due in Dubuque Saturday at 12 o'clock. 
A follow-up story appeared on page 1, Sunday, July 30, 1911
STEAMER ST. PAUL NOW IN DRYDOCK
Craft That Ran Onto Snag Is Floated--Damage to Hull Is Slight
WILL ABANDON ONE TRIP
Reaches St. Louis Early This Week and Resumes Schedule, Arriving in Dubuque--August 8th.
Quincy, Ill., July 29--Special.  At 1:24 this afternoon the St. Paul was floated and proceeded north with the intention of reaching drydocks at Keokuk.  Carpenters worked all day yesterday and all night building bulkheads around the holes and almost floated the craft last night when a heavy windstorm again grounded her.  The passengers were composed until the storm of last night struck.  Women, too nervous to go to bed, sat huddled together on the boiler deck (this is actually the second deck on the boat where staterooms and the main cabin were located, not the main deck where the boilers and engines are situated).
At the Dubuque headquarters of the Streckfus company it was announced last last night the St. Paul had reached Keokuk and had been placed on the ways.  The damage to the boat is of a nature that will require very little time in repairing and it was confidently predicted the boat will be on her way south before Monday  morning.  She will return to St. Louis instead of continuing the trip north.
The St. Paul was scheduled to arrive in Dubuque yesterday.  What the management has decided to do is to abandon the present trip and start out from St. Louis and carry out the schedule of the next trip, arriving in Dubuque August 8.
It was stated at the local headquarters the stage of water will not bother the St. Paul.  The stage is on the rise with prospects of continuing the upward movement.  The boat draws but three feet.
The passengers on board the boat when she struck the snag near Quincy all were landed and sent by rail to their destinations, many of them returning to St. Louis.
 
The Str. St. Paul, along with the steamers Quincy, Dubuque and Sidney, were all packets, carrying both freight and passengers between St. Paul and St. Louis.  This was the trade in which the Diamond Jo Line operated, and that Streckfus continued for a short while, until the long haul freight and passenger trade began to die out on the river.  With that, Streckfus began to convert some of its boats into excursion steamers, keeping only two fo the boats running as packets.  The Str. St. Paul, biggest of the steamboats Streckfus owned, was the first to be converted to the excursion trade as this story in the next year's paper reported on Wednesday, February 7, 1912, page 10:
ST. PAUL BECOMES EXCURSION BOAT
Streckfus Steamboat Company Decides to Use Big Packet in This Trade
Dubuquers will be interested in the announcement by the officers of Streckfus Steamboat Company, in session at Rock Island (Illinois), that the packet St. Paul, said to be the largest boat on the upper river, will be placed in the excursion business early in the Spring.  The St. Paul is perhaps the most widely known steamer plying the waters of the Mississippi, and up to the present Winter has been tied up in the ice harbor here during the off season.  The Rock Island Daily Union says:
Plans for the summer season of the Streckfus Steamboat lline are being made today by the officers, in session here.  It has been decided to put the steamer St. Paul in the excursion business early in the Spring and operated the boat as an excursion steamer till late in the summer when the packet trade demands the services of the boat.  The St. Paul is to be considerably remodeled to fit it for excursion work, and the cabin will be enlarged and some of the state rooms will be removed.  The steamer, however, will still have ample accomodations to fit it for the packet service when the trade requires the operation of a second boat.  The St. Paul is the largest boat on the upper river (276 feet long, 37 feet wide), and it will be fitted out as a luxurious excursion craft.
 
There was one final story about the St. Paul which I've included from the Friday, June 21, 1912, issue of the Dubuque Telegraph-Herald, page 14:
Excursionists out of Dubuque were treated to a steamboat race Thursday morning between the Streckfus Line steamer Quincy (sic) (should say St. Paul) and the Wisherd Line steamer G. W. Hill.  The  two boats left the levee at almost exactly the same instant, the Hill with the St. Luke's Methodist Episcopal Church excursion bound for Cassville and the (St. Paul) with the Military Band excursion bound for Guttenberg.  The St. Paul cleared first and whistled for the draw bridge which swung open just barely in time to let the both boats through, the St. Paul slightly in the lead.  Side by side the two boats raced from the lower to the upper bridge, the steam roaring through their stacks and their crews shouting insulting remarks to each other regarding the speed of each boat.  At Eagle Point (the extreme north end of the city), the Hill, which is a new boat and one of the fastest on the upper river, began to show its superiority and the better craft of its pilot and its captain, J. R. Trombley, of Dubuque, and began to forge ahead, a few inches at a time, until finally clear water showed between the Hill's stern and the St. Paul's bow.  Steadily the Hill pulled ahead, until it landed in Cassville nearly three-quarters of a mile ahead of the St. Paul, which steamed on ahead to Guttenberg.
 
The next story I located mentions Capt. McGee by name only briefly, but it does give us a definite clue as to which steamer he served on that season.  The story appears on page 9 of the Friday, April 18, 1913, Dubuque Telegraph-Herald:
Captain R. H. Trombley (of Dubuque), veteran steamboat captain and pilot, will be in charge of the excursion steamer Frontenac this coming summer.
Captain Trombley, who last season was commander of the excursion steamer G. W. Hill, looks for an excellent season on the river.
Captain Trombley has compiled the following list of steamers which will be seen on the upper river this season and the names of their captains, as follows:
St. Paul-John Streckfus; Quincy-Connie McGee; Dubuque-Bill Simmons; Sidney-Roy Streckfus; W.W.-Louis Muntz; Morning Star-Walter Blair; Helen Blair-Ziprian Buisson; Keokuk-Hugh McKenzie; Black Hawk-Rob Dodds; G. W. Hill-Walter Wisherd; Frontenac-R. H. Trombley; Ottumwa Belle-Walter Hunter; Clyde-Ike Newcomb; Elinor-Ben Metzger; Ruth-Doss Holsapple; Brusso-George Trombley; Lone Star-John McDonald; Red Wing-Milt Newcomb.
As you can see, there were only about nineteen steamboats left on the entire upper Mississippi in 1913, and so your grandfather was among the elite few to captain a steamboat at this time.  The first five boats in that list all belonged to Streckfus Steamers.  According to Capt. Trombley's list, Capt. McGee had been put in command of the big packet sidewheeler Quincy, while Capt. John Streckfus, founder and owner of Streckfus Steamboat Line, was himself in charge of the St. Paul.  Roy Streckfus, captain on the Sidney, was one of John's sons.