How could a make an object something that could be jumped over? The best I could come up with is supporter but that didn’t fly.
Deep river is here. It is a supporter.
After jumping over Deep River:
say "You jump over as best you can and nearly drown because it is as the name indicates really deep. Also the skinhead woman up on Todd Bridge throws rocks at you. But at least you still have all of your money and most of your dignity.";
now the player is in love weeds.
The standard rules only have a “jump” action, with no object specified.
You will have to create a new “jumping over” action. See chapter 12.7.
Here’s an example of the two approaches you can take to have the player jump over thing.
The first approach is to modify the behavior of the built in jumping action, the second is to define a new action, in this case called jumping over.
"Jumping over it"
The river bed is a room. The deep river is here.
Carry out jumping when the deep river is in the location of the player:
say "You jump over as best you can and nearly drown because it is as the name indicates really deep. Also the skinhead woman up on Todd Bridge throws rocks at you. But at least you still have all of your money and most of your dignity.";
now the player is in love weeds;
stop the action [this stops the default report jumping rule].
The love weeds is a room.
Jumping over is an action applying to one thing.
Understand "Jump over [a thing]" as jumping over.
Check jumping over something(called the thing jumped over) when the thing jumped over is not the deep river(this is the can't jump over things that aren't the deep river rule):
say "You don't think you'll be able to jump over that".
Carry out jumping over the deep river:
say "You jump over as best you can and nearly drown because it is as the name indicates really deep. Also the skinhead woman up on Todd Bridge throws rocks at you. But at least you still have all of your money and most of your dignity.";
now the player is in love weeds.IMVHO, if the thing to be jumped over is only one or two, perhaps the new action is an overkill, and is easier tackling the coding problem as an instead of jumping… in the appropriate location(s).
Best regards from Italy,
dott. Piergiorgio.
Another option is giving feedback on player movement.
West Shore is a room.
The description of the west shore is "This sandy patch of gravel and smooth, rounded stones floods whenever the rains get heavy. To the east is a stream that appears crossable.".
Love Weeds is east of west shore.
The description of Love Weeds is "Stunted shrubs reach out of the sandy soil. Flood waters regularly pick this earth clean. To the west a wide stream tumbles over small stones. You could probably cross it here.".
Carry out going east in west shore:
say "[if Love Weeds is unvisited]You jump over as best you can and nearly drown because it is as the name indicates really deep. Also the skinhead woman up on Todd Bridge throws rocks at you. But at least you still have all of your money and most of your dignity.[otherwise]You awkwardly jump into the Love Weeds.";
continue the action.
Carry out going west in Love Weeds:
say "You splash and fumble your way to the west shore.".
Interesting, drew, but what about the skinhead woman’s reaction against an easy target as an adventurer wading a stream ? 
Best regards from Italy,
dott. Piergiorgio.