diff --git a/README.txt b/README.txt
index d0d33cf..9c62cef 100644
--- a/README.txt
+++ b/README.txt
@@ -136,6 +136,10 @@ A ringing bell indicates that there are insufficient materials in inventory to s
 
 A short high-pitched honk means that one or more of the builder heads don't have an item set. A common oversight, especially with large and elaborate digging machines, that might be hard to notice and annoying to fix if not noticed right away.
 
+Splooshing water sounds means your Digtron is digging adjacent to (or through) water-containing nodes. Digtrons are waterproof, but this might be a useful indication that you should take care when installing doors in the tunnel walls you've placed here.
+
+A triple "voop voop voop!" alarm indicates that there is lava adjacent to your Digtron. Digtrons can't penetrate lava by default, and although they are not destroyed by lava this alarm indicates that a non-lava-proof Digtron operator may wish to exercise caution when backing up.
+
 Crafting recipes
 ================
 
diff --git a/init.lua b/init.lua
index fc18dc6..1576130 100644
--- a/init.lua
+++ b/init.lua
@@ -7,8 +7,9 @@ dofile( minetest.get_modpath( "digtron" ) .. "/node_builders.lua" ) -- contains
 dofile( minetest.get_modpath( "digtron" ) .. "/node_controllers.lua" ) -- controllers
 dofile( minetest.get_modpath( "digtron" ) .."/recipes.lua" )
 
-digtron.creative_mode = false
-digtron.particle_effects = true
+digtron.creative_mode = false -- this causes digtrons to operate without consuming fuel or building materials.
+digtron.particle_effects = true -- Enables the spray of particles out the back of a digger head
+digtron.lava_impassible = true -- when true, lava counts as protected nodes.
 
 digtron.cycle_time = 1 -- How many seconds a digtron waits between cycles. Auto-controllers can make this wait longer, but cannot make it shorter.
 digtron.traction_factor = 3.0 -- How many digtron nodes can be moved for each adjacent solid node that the digtron has traction against
diff --git a/node_controllers.lua b/node_controllers.lua
index cfd449b..c897502 100644
--- a/node_controllers.lua
+++ b/node_controllers.lua
@@ -32,6 +32,12 @@ local execute_cycle = function(pos, clicker)
 		return pos, "Digtron is adjacent to unloaded nodes.\n" .. status_text
 	end
 	
+	if layout.water_touching == true then
+		minetest.sound_play("sploosh", {gain=1.0, pos=pos})
+	end
+	if layout.lava_touching == true then
+		minetest.sound_play("woopwoopwoop", {gain=1.0, pos=pos})
+	end	
 	if layout.traction * digtron.traction_factor < table.getn(layout.all) then
 		-- digtrons can't fly
 		minetest.sound_play("squeal", {gain=1.0, pos=pos})
diff --git a/sounds/license.txt b/sounds/license.txt
index 77f5a88..165e797 100644
--- a/sounds/license.txt
+++ b/sounds/license.txt
@@ -6,6 +6,8 @@ dingding.ogg - https://www.freesound.org/people/JohnsonBrandEditing/sounds/17393
 squeal.ogg - https://www.freesound.org/people/RutgerMuller/sounds/104026/ public domain via CC 1.0 by RutgerMuller
 honk.ogg - https://freesound.org/people/bigmanjoe/sounds/349922/ public domain via CC 1.0 by bigmanjoe
 truck.ogg - https://www.freesound.org/people/jberkuta14/sounds/134898/ public domain via CC 1.0 by jberkuta14
+sploosh.ogg - https://www.freesound.org/people/mr_marcello/sounds/257609/ public domain via CC 1.0 by mr_marcello
+woopwoopwoop.ogg - https://www.freesound.org/people/gregconquest/sounds/188012/ public domain via CC 1.0 by gregconquest
 
 
 Creative Commons Attribution 3.0 license:
diff --git a/sounds/sploosh.ogg b/sounds/sploosh.ogg
new file mode 100644
index 0000000..5e7a226
Binary files /dev/null and b/sounds/sploosh.ogg differ
diff --git a/sounds/woopwoopwoop.ogg b/sounds/woopwoopwoop.ogg
new file mode 100644
index 0000000..beb26be
Binary files /dev/null and b/sounds/woopwoopwoop.ogg differ
diff --git a/util.lua b/util.lua
index 2c1c967..a74f21f 100644
--- a/util.lua
+++ b/util.lua
@@ -138,6 +138,8 @@ digtron.get_all_digtron_neighbours = function(pos, player)
 	layout.diggers = {}
 	layout.builders = {}
 	layout.extents = {}
+	layout.water_touching = false
+	layout.lava_touching = false
 	layout.protected = Pointset.create() -- if any nodes we look at are protected, make note of that. That way we don't need to keep re-testing protection state later.
 	layout.controller = {x=pos.x, y=pos.y, z=pos.z} 	--Make a deep copy of the pos parameter just in case the calling code wants to play silly buggers with it
 
@@ -182,6 +184,15 @@ digtron.get_all_digtron_neighbours = function(pos, player)
 			layout.protected:set(testpos.x, testpos.y, testpos.z, true)
 		end
 		
+		if minetest.get_item_group(node.name, "water") ~= 0 then
+			layout.water_touching = true
+		elseif minetest.get_item_group(node.name, "lava") ~= 0 then
+			layout.lava_touching = true
+			if digtron.lava_impassible == true then
+				layout.protected:set(testpos.x, testpos.y, testpos.z, true)
+			end
+		end
+		
 		local group_number = minetest.get_item_group(node.name, "digtron")
 		if group_number > 0 then
 			--found one. Add it to the digtrons output