Digging a hole

[Alzrius]

As a tactic, my group has decided to construct some basic defenses when camping out in the wild. One such defense is to dig pits around where we bed down for the night. However, we're having a hard time figuring out how long doing so takes, and if it'd require any sort of check or die roll.

All I can find in the SRD about digging is the following, regarding cave-ins and collapses in dungeons:

In 1 minute, using only her hands, a character can clear rocks and debris equal to five times her heavy load limit. The amount of loose stone that fills a 5-foot-by-5-foot area weighs one ton (2,000 pounds). Armed with an appropriate tool, such as a pick, crowbar, or shovel, a digger can clear loose stone twice as quickly as by hand.

This isn't very helpful for trying to figure out the rate at which a character with a shovel can dig a 10-foot hole in a 5-foot square area.

We're also considering camouflaging the pit, and putting in spikes as well. Presumably, at some point - probably when adding the camo and/or spikes - this will require the Craft (trapmaking) skill, which nobody has. I'm assuming that they'll just need to make an untrained Craft (trapmaking) check at that point, right?

EDIT: Another issue is creating cover around their encampment. Presuming they can use dirt from digging holes, how much (that is, how many 5-foot square, 10-foot deep holes' worth) of dirt and surrounding debris are necessary to create low obstacles for cover? How long would it take to make them for a 5-foot square (presumably it wouldn't take up the square, would it)?

 

[Doug Sundseth]

I don't know of any canonical answer, so I'll just give my thoughts:

If you are strong and adept with a pick and shovel (you will need both), you might just possibly be able to dig a single 5' x 5' x 10' hole in plowed earth in 8 hours. You could dig out that much sand in less time, but you wouldn't have a hole of the sort you describe at the end of the process.

If there are rocks in the earth (and there nearly always are when you get more than a couple of feet below the surface) or if the earth is hard or there is significant turf, the process will be much slower.

 

[TessarrianDM]

A 5' x 5' x 10' pit contains 250 cubic feet of material. Basing it on Gary Gygax's World Builder book, and rounding up his figure of 124 lbs./cu. ft. to 125 lbs., it contains 31,250 pounds of common soil. I would allow a character to dig an amount equal to his heavy load maximum in 1 minute using a shovel (this accounts for roots, rocks, compaction, etc.).

This would mean a character with a Str 10 could dig the hole in 5 hours 12 min. One with Str 15 would take 2 hours 36 min; Str 18 @ 1 hour 45 min; Str 20 @ 1 hour 18 min; Str 24 @ 45 min.

Each hole would generate a wall of dirt approximately 4' high, 4' thick, and 15' long (using 240 cu. ft. of the 250 cu. ft. from the hole). I would double the digging time per pit to account for the construction of the wall/cover.

Hiding the pits would require a Disguise check (opposed by Spot or Search) and take 1d8x10 minutes per pit (Rules Compendium pg. 106, Disguising Objects).

The base DC to craft a simple mechanical trap (DMG pg. 76) of CR 1-3 (your average pit) is 20; if no one has craft (trapmaking), I would probably make that a DC 25 (the DC for a CR 4-6 trap).

 

[Alzrius]

TessarrianDM, thanks for the thoughtful reply! I wanted to go over some of your answers below.

I would double the digging time per pit to account for the construction of the wall/cover.

The plan is for other party members to do this. Considering it as a separate activity, how much time do you think it would take?

Hiding the pits would require a Disguise check (opposed by Spot or Search) and take 1d8x10 minutes per pit (Rules Compendium pg. 106, Disguising Objects).

I think this falls under the Craft (trapmaking) skill more than Disguise, because the SRD explicitly lists a camouflaged pit trap as a type of trap, and the section on pits says that a covered pit counts as one that is hidden by refuse (which it says are straw, leaves, sticks, and garbage).

The base DC to craft a simple mechanical trap (DMG pg. 76) of CR 1-3 (your average pit) is 20; if no one has craft (trapmaking), I would probably make that a DC 25 (the DC for a CR 4-6 trap).

I don't see anything in the RAW that'd make the DC go up if the check was untrained.

 

[Darkwolf71]

I think this falls under the Craft (trapmaking) skill more than Disguise, because the SRD explicitly lists a camouflaged pit trap as a type of trap, and the section on pits says that a covered pit counts as one that is hidden by refuse (which it says are straw, leaves, sticks, and garbage).

I think I'd make an argument for Survival. Craft (trapmaking) IMHO is intended for mechanical type traps more than makeshift ones. Besides, who would expect your average Ranger to have Craft (trapmaking).


As for the movement of earth, having dug a roughly 5x5x10 foot hole before, I think TessarrianDM's estimates are very generous. I'd be curious as to what the numbers look like for light and medium load based calculations.

I'm thinking the results should realisticaly be at least double what he figured for a Max load base.

 

[Jhaelen]

As a tactic, my group has decided to construct some basic defenses when camping out in the wild. One such defense is to dig pits around where we bed down for the night. However, we're having a hard time figuring out how long doing so takes, and if it'd require any sort of check or die roll.

Invite them to a live action experiment. Let them try to dig a trench and see how long it takes for them to give up on the practice

In my totally unqualified opinion, creating basic defenses for a camp that are sufficient to have a meaningful effect should the camp be attacked, will take a collective effort of 8 hours, minimum. Basically, the party would only be able to travel every other day.

 

[Alzrius]

I know that altering the terrain to any appreciable degree (such as digging holes) is extremely difficult and time-consuming in real life. But that's a simulationist stance, not a gamist one. Strictly speaking, you can't keep fighting for long before you become tired, but in the d20 System a character can fight forever, until they start taking penalties for not stopping to eat or sleep.

I'm trying to find a reasonable baseline within the existing framework of the rules for how to dig pit traps, and create cover from displaced dirt and debris.

 

[Darkwolf71]

Yeah, I get that a lot.

I suppose TDMs numbers work well for a game. (There, I said it. )

I still think Survival would be a more appropriate skill check though.

 

[TessarrianDM]

TessarrianDM, thanks for the thoughtful reply! I wanted to go over some of your answers below.



The plan is for other party members to do this. Considering it as a separate activity, how much time do you think it would take?

I think this falls under the Craft (trapmaking) skill more than Disguise, because the SRD explicitly lists a camouflaged pit trap as a type of trap, and the section on pits says that a covered pit counts as one that is hidden by refuse (which it says are straw, leaves, sticks, and garbage).

I don't see anything in the RAW that'd make the DC go up if the check was untrained.

a. You're welcome!

b. It really depends on how many people are working on it. I would allow a group of four to dig the pits and build the wall/cover all at the same time, in the amount of time required to dig the pits. I wouldn't want to get into calculating how far they are carrying the dirt, how much they are carrying at one time, etc. Too much of a hassle.

c. Yes, it could. However, if you wanted to go by that, why not just use Craft skill checks and the rules for building traps in the DMG? They would qualify as CR 1 pit traps, it but would take a lot longer to build using this method. Even if you rolled a natural 20 and had an 18 Int you would only get 480 sp worth of trap built in a week; a CR 1 camouflaged pit trap has a price of 1800 gp, requiring 37.5 weeks of work (if you rolled a 20 on every check)! I was looking at it more from a makeshift "let's get this done quick" point of view.

d. No, there isn't, and I can see your point. A DC of 20 should be sufficient.


Darkwolf71, as far as the times go, the amount of time it takes a PC with a Str 10 to clear a loose rock cave-in 5' x 5' x 5' with no tools would be 4 minutes (100 lb heavy load x 5 = 500 lbs./minute) according to the SRD (see OP), 2 minutes with a shovel. Going by that formula , the same PC could dig out a 5' x 5' x 10' deep pit full of loose rock in 8 minutes by hand. My times may be generous but not as generous as this!

 

[roguerouge]

Don't forget that these figures should account for exhaustion effects. Supposedly, the PCs are doing this after a long day of travel (complete with one wandering monster) or adventuring (with much fighting) or both. I'd throw in some Endurance feat style checks.

Really, accomplishing this sort of thing is what hirelings are for and what armies used to use slaves or raw recruits for. If the PCs are trying to do this stuff, tell them to hire someone to do it for them.