diff --git a/Substrate/SubstrateCS/Source/AlphaBlockCollection.cs b/Substrate/SubstrateCS/Source/AlphaBlockCollection.cs
index e1b7cc5..e93dcf3 100644
--- a/Substrate/SubstrateCS/Source/AlphaBlockCollection.cs
+++ b/Substrate/SubstrateCS/Source/AlphaBlockCollection.cs
@@ -57,6 +57,7 @@ namespace Substrate
         private TagList _tileEntities;
 
         private BlockLight _lightManager;
+        private BlockFluid _fluidManager;
         private BlockTileEntities _tileEntityManager;
 
         private bool _dirty = false;
@@ -71,11 +72,16 @@ namespace Substrate
                 _lightManager.ResolveNeighbor += delegate(int relx, int rely, int relz) { 
                     return value(relx, rely, relz); 
                 };
+                _fluidManager.ResolveNeighbor += delegate(int relx, int rely, int relz)
+                {
+                    return value(relx, rely, relz);
+                };
             }
 
             remove
             {
                 _lightManager = new BlockLight(this);
+                _fluidManager = new BlockFluid(this);
             }
         }
 
@@ -107,6 +113,7 @@ namespace Substrate
             _tileEntities = properties.tileEntities;
 
             _lightManager = new BlockLight(this);
+            _fluidManager = new BlockFluid(this);
             _tileEntityManager = new BlockTileEntities(_blocks, _tileEntities);
         }
 
@@ -452,6 +459,16 @@ namespace Substrate
 
         #endregion
 
+        public void ResetBlockFluid ()
+        {
+            _fluidManager.ResetWater();
+            _dirty = true;
+        }
 
+        public void RebuildBlockFluid ()
+        {
+            _fluidManager.RebuildWater();
+            _dirty = true;
+        }
     }
 }
diff --git a/Substrate/SubstrateCS/Source/BlockFluid.cs b/Substrate/SubstrateCS/Source/BlockFluid.cs
new file mode 100644
index 0000000..a43678e
--- /dev/null
+++ b/Substrate/SubstrateCS/Source/BlockFluid.cs
@@ -0,0 +1,321 @@
+using System;
+using System.Collections.Generic;
+
+namespace Substrate
+{
+    using Utility;
+
+    public class BlockFluid
+    {
+        private IBoundedDataBlockCollection _blockset;
+
+        private readonly int _xdim;
+        private readonly int _ydim;
+        private readonly int _zdim;
+
+        private Dictionary<ChunkKey, IBoundedDataBlockCollection> _chunks;
+
+        public delegate IBoundedDataBlockCollection NeighborLookupHandler (int relx, int rely, int relz);
+
+        public event NeighborLookupHandler ResolveNeighbor;
+
+        internal class BlockCoord
+        {
+            internal IBoundedDataBlockCollection chunk;
+            internal int lx;
+            internal int ly;
+            internal int lz;
+
+            internal BlockCoord (IBoundedDataBlockCollection _chunk, int _lx, int _ly, int _lz)
+            {
+                chunk = _chunk;
+                lx = _lx;
+                ly = _ly;
+                lz = _lz;
+            }
+        }
+
+        public BlockFluid (IBoundedDataBlockCollection blockset)
+        {
+            _blockset = blockset;
+
+            _xdim = _blockset.XDim;
+            _ydim = _blockset.YDim;
+            _zdim = _blockset.ZDim;
+
+            _chunks = new Dictionary<ChunkKey,IBoundedDataBlockCollection>();
+        }
+
+        public BlockFluid (BlockFluid bl)
+        {
+            _blockset = bl._blockset;
+
+            _xdim = bl._xdim;
+            _ydim = bl._ydim;
+            _zdim = bl._zdim;
+
+            _chunks = new Dictionary<ChunkKey, IBoundedDataBlockCollection>();
+        }
+
+        public void ResetWater ()
+        {
+            int xdim = _xdim;
+            int ydim = _ydim;
+            int zdim = _zdim;
+
+            for (int x = 0; x < xdim; x++) {
+                for (int z = 0; z < zdim; z++) {
+                    for (int y = 0; y < ydim; y++) {
+                        IDataBlock block = _blockset.GetBlockRef(x, y, z);
+                        if ((block.ID == BlockType.STATIONARY_WATER || block.ID == BlockType.WATER) && block.Data != (int)WaterFlow.FULL) {
+                            block.ID = BlockType.AIR;
+                            block.Data = 0;
+                        }
+                        else if (block.ID == BlockType.WATER) {
+                            block.ID = BlockType.STATIONARY_WATER;
+                        }
+                    }
+                }
+            }
+        }
+
+        public void RebuildWater ()
+        {
+            int xdim = _xdim;
+            int ydim = _ydim;
+            int zdim = _zdim;
+
+            List<BlockKey> buildQueue = new List<BlockKey>();
+
+            for (int x = 0; x < xdim; x++) {
+                for (int z = 0; z < zdim; z++) {
+                    for (int y = 0; y < ydim; y++) {
+                        BlockInfo info = _blockset.GetInfo(x, y, z);
+                        if (info.ID == BlockType.STATIONARY_WATER && _blockset.GetData(x, y, z) == (int)WaterFlow.FULL) {
+                            buildQueue.Add(new BlockKey(x, y, z));
+                        }
+                    }
+                }
+            }
+
+            foreach (BlockKey key in buildQueue) {
+                SpreadWater(key.x, key.y, key.z);
+            }
+        }
+
+        private void SpreadWater (int x, int y, int z)
+        {
+            Queue<KeyValuePair<BlockKey, int>> targets = new Queue<KeyValuePair<BlockKey, int>>();
+            targets.Enqueue(new KeyValuePair<BlockKey, int>(new BlockKey(x, y, z), 0));
+
+            while (targets.Count > 0) {
+                KeyValuePair<BlockKey, int> skey = targets.Dequeue();
+
+                BlockKey source = skey.Key;
+                int sourceDist = skey.Value;
+ 
+                int nearestDrop = 7;
+                bool foundDrop = false;
+
+                Queue<BlockKey> searchQueue = new Queue<BlockKey>();
+                Queue<KeyValuePair<BlockKey, int>> sinkQueue = new Queue<KeyValuePair<BlockKey, int>>();
+                Dictionary<BlockKey, int> marked = new Dictionary<BlockKey, int>();
+
+                searchQueue.Enqueue(source);
+                marked.Add(source, sourceDist);
+
+                // Identify sinks
+                while (searchQueue.Count > 0) {
+                    BlockKey branch = searchQueue.Dequeue();
+                    int distance = marked[branch] & ~(int)LiquidState.FALLING;
+                    bool falling = (marked[branch] & (int)LiquidState.FALLING) > 0;
+
+                    // Ignore blocks out of range
+                    if (distance > nearestDrop) {
+                        continue;
+                    }
+
+                    // Ignore invalid blocks
+                    BlockCoord branchHigh = TranslateCoord(branch.x, branch.y, branch.z);
+                    if (branchHigh.chunk == null || branch.y == 0) {
+                        marked.Remove(branch);
+                        continue;
+                    }
+
+                    // If we're not the magical source block...
+                    if (distance > 0 && !falling) {
+                        // Ignore blocks that block fluid (and thus could not become a fluid)
+                        BlockInfo branchHighInfo = branchHigh.chunk.GetInfo(branchHigh.lx, branchHigh.ly, branchHigh.lz);
+                        if (branchHighInfo.BlocksFluid) {
+                            marked.Remove(branch);
+                            continue;
+                        }
+
+                        // Ignore blocks that have a "fuller" fluid level
+                        if (branchHighInfo.ID == BlockType.STATIONARY_WATER) {
+                            int cmp = branchHigh.chunk.GetData(branchHigh.lx, branchHigh.ly, branchHigh.lz);
+                            if (cmp <= distance || (cmp & (int)LiquidState.FALLING) > 0) {
+                                marked.Remove(branch);
+                                continue;
+                            }
+                        }
+                    }
+
+                    // If we found a hole, add as a sink, mark the sink distance.
+                    BlockCoord branchLow = TranslateCoord(branch.x, branch.y - 1, branch.z);
+                    BlockInfo branchLowInfo = branchLow.chunk.GetInfo(branchLow.lx, branchLow.ly, branchLow.lz);
+                    if (!branchLowInfo.BlocksFluid) {
+                        foundDrop = true;
+                        nearestDrop = falling ? 0 : distance;
+                        sinkQueue.Enqueue(new KeyValuePair<BlockKey, int>(branch, falling ? distance | (int)LiquidState.FALLING : distance));
+                        continue;
+                    }
+
+                    // Didn't find a hole, hit the bottom, reset distance
+                    if (falling) {
+                        distance = 0;
+                    }
+
+                    // Expand to neighbors
+                    if (distance < nearestDrop) {
+                        BlockKey[] keys = {
+                            new BlockKey(branch.x - 1, branch.y, branch.z),
+                            new BlockKey(branch.x + 1, branch.y, branch.z),
+                            new BlockKey(branch.x, branch.y, branch.z - 1),
+                            new BlockKey(branch.x, branch.y, branch.z + 1),
+                        };
+                        
+                        for (int i = 0; i < 4; i++) {
+                            if (!marked.ContainsKey(keys[i])) {
+                                searchQueue.Enqueue(keys[i]);
+                                marked.Add(keys[i], distance + 1);
+                            }
+                        }
+                    }
+                }
+
+                // If we didn't find any drops, fill out the mark table
+                if (!foundDrop) {
+                    foreach (KeyValuePair<BlockKey, int> mark in marked) {
+                        BlockKey target = mark.Key;
+
+                        BlockCoord targetHigh = TranslateCoord(target.x, target.y, target.z);
+                        targetHigh.chunk.SetID(targetHigh.lx, targetHigh.ly, targetHigh.lz, BlockType.STATIONARY_WATER);
+                        targetHigh.chunk.SetData(targetHigh.lx, targetHigh.ly, targetHigh.lz, mark.Value);
+                    }
+
+                    // Skip sinks and tracing
+                    continue;
+                }
+
+                // Create new target for each sink
+                Queue<KeyValuePair<BlockKey, int>> traceQueue = new Queue<KeyValuePair<BlockKey, int>>();
+                while (sinkQueue.Count > 0) {
+                    KeyValuePair<BlockKey, int> tkey = sinkQueue.Dequeue();
+                    BlockKey target = tkey.Key;
+                    int distance = tkey.Value;
+
+                    //int distance = marked[target];
+                    marked.Remove(target);
+
+                    targets.Enqueue(new KeyValuePair<BlockKey, int>(new BlockKey(target.x, target.y - 1, target.z), distance | (int)LiquidState.FALLING));
+                    traceQueue.Enqueue(new KeyValuePair<BlockKey, int>(target, distance));
+
+                    /*BlockCoord targetLow = TranslateCoord(target.x, target.y - 1, target.z);
+                    targetLow.chunk.SetID(targetLow.lx, targetLow.ly, targetHigh.lz, BlockType.STATIONARY_WATER);
+                    targetLow.chunk.SetData(targetLow.lx, targetLow.ly, targetHigh.lz, tkey.Value);*/
+                }
+
+                // Trace back from sinks
+                while (traceQueue.Count > 0) {
+                    KeyValuePair<BlockKey, int> tkey = traceQueue.Dequeue();
+
+                    BlockKey target = tkey.Key;
+                    int distance = tkey.Value & ~(int)LiquidState.FALLING;
+                    bool falling = (tkey.Value & (int)LiquidState.FALLING) > 0;
+
+                    //if (distance == 0) {
+                    //   distance |= (int)LiquidState.FALLING;
+                    //}
+
+                    BlockCoord targetHigh = TranslateCoord(target.x, target.y, target.z);
+                    targetHigh.chunk.SetID(targetHigh.lx, targetHigh.ly, targetHigh.lz, BlockType.STATIONARY_WATER);
+                    targetHigh.chunk.SetData(targetHigh.lx, targetHigh.ly, targetHigh.lz, tkey.Value);
+
+                    if (falling) {
+                        continue;
+                    }
+
+                    BlockKey[] keys = {
+                        new BlockKey(target.x - 1, target.y, target.z),
+                        new BlockKey(target.x + 1, target.y, target.z),
+                        new BlockKey(target.x, target.y, target.z - 1),
+                        new BlockKey(target.x, target.y, target.z + 1),
+                    };
+
+                    for (int i = 0; i < 4; i++) {
+                        int nval;
+                        if (!marked.TryGetValue(keys[i], out nval)) {
+                            continue;
+                        }
+
+                        int ndist = nval & ~(int)LiquidState.FALLING;
+                        bool nfall = (nval & (int)LiquidState.FALLING) > 0;
+
+                        marked.Remove(keys[i]);
+                        if (ndist < distance || nfall) {
+                            traceQueue.Enqueue(new KeyValuePair<BlockKey, int>(keys[i], nval));
+                        }
+                    }
+                }
+            }
+        }
+
+        private BlockCoord TranslateCoord (int x, int y, int z)
+        {
+            IBoundedDataBlockCollection chunk = GetChunk(x, z);
+
+            int lx = ((x % _xdim) + _xdim) % _xdim;
+            int lz = ((z % _zdim) + _zdim) % _zdim;
+
+            return new BlockCoord(chunk, lx, y, lz);
+        }
+
+        private IBoundedDataBlockCollection GetChunk (int x, int z)
+        {
+            int cx = x / _xdim + (x >> 31);
+            int cz = z / _zdim + (z >> 31);
+
+            ChunkKey key = new ChunkKey(cx, cz);
+
+            IBoundedDataBlockCollection chunk;
+            if (!_chunks.TryGetValue(key, out chunk)) {
+                chunk = OnResolveNeighbor(cx, 0, cz);
+                _chunks[key] = chunk;
+            }
+
+            return chunk;
+        }
+
+        private IBoundedDataBlockCollection OnResolveNeighbor (int relX, int relY, int relZ)
+        {
+            if (ResolveNeighbor != null) {
+                IBoundedDataBlockCollection n = ResolveNeighbor(relX, relY, relZ);
+
+                if (n == null) {
+                    return null;
+                }
+
+                if (n.XDim != _xdim ||
+                    n.YDim != _ydim ||
+                    n.ZDim != _zdim) {
+                        throw new InvalidOperationException("Subscriber returned incompatible IDataBlockCollection");
+                }
+
+                return n;
+            }
+
+            return null;
+        }
+    }
+}
diff --git a/Substrate/SubstrateCS/Source/BlockInfo.cs b/Substrate/SubstrateCS/Source/BlockInfo.cs
index 1dbde42..d818b8a 100644
--- a/Substrate/SubstrateCS/Source/BlockInfo.cs
+++ b/Substrate/SubstrateCS/Source/BlockInfo.cs
@@ -178,6 +178,7 @@ namespace Substrate
         private int _opacity = MAX_OPACITY;
         private int _luminance = MIN_LUMINANCE;
         private bool _transmitLight = false;
+        private bool _blocksFluid = true;
 
         private BlockState _state = BlockState.SOLID;
 
@@ -221,6 +222,11 @@ namespace Substrate
             get { return _opacity > MIN_OPACITY || !_transmitLight; }
         }
 
+        public bool BlocksFluid
+        {
+            get { return _blocksFluid; }
+        }
+
         public BlockState State
         {
             get { return _state; }
@@ -276,6 +282,20 @@ namespace Substrate
         public BlockInfo SetState (BlockState state)
         {
             _state = state;
+
+            if (_state == BlockState.SOLID) {
+                _blocksFluid = true;
+            }
+            else {
+                _blocksFluid = false;
+            }
+
+            return this;
+        }
+
+        public BlockInfo SetBlocksFluid (bool blocks)
+        {
+            _blocksFluid = blocks;
             return this;
         }
 
@@ -500,6 +520,12 @@ namespace Substrate
             Farmland.SetLightTransmission(false);
             CobbleStairs.SetLightTransmission(false);
 
+            // Override default fluid blocking rules
+
+            SignPost.SetBlocksFluid(true);
+            WallSign.SetBlocksFluid(true);
+            Cactus.SetBlocksFluid(false);
+
             // Set Tile Entity Data
 
             Dispenser.SetTileEntity("Trap");
diff --git a/Substrate/SubstrateCS/Source/BlockLight.cs b/Substrate/SubstrateCS/Source/BlockLight.cs
index 0afd08f..4440f9f 100644
--- a/Substrate/SubstrateCS/Source/BlockLight.cs
+++ b/Substrate/SubstrateCS/Source/BlockLight.cs
@@ -68,7 +68,7 @@ namespace Substrate
             BlockKey primary = new BlockKey(lx, ly, lz);
             _update.Enqueue(primary);
 
-            BlockInfo info = _blockset.GetInfo(lx, ly, lz);
+            //BlockInfo info = _blockset.GetInfo(lx, ly, lz);
 
             //if (info.Luminance > BlockInfo.MIN_LUMINANCE || info.TransmitsLight) {
             if (ly > 0) {
diff --git a/Substrate/SubstrateCS/Source/ChunkKey.cs b/Substrate/SubstrateCS/Source/ChunkKey.cs
index 267f483..3c44323 100644
--- a/Substrate/SubstrateCS/Source/ChunkKey.cs
+++ b/Substrate/SubstrateCS/Source/ChunkKey.cs
@@ -6,8 +6,8 @@ namespace Substrate
 {
     public struct ChunkKey : IEquatable<ChunkKey>
     {
-        readonly int cx;
-        readonly int cz;
+        public readonly int cx;
+        public readonly int cz;
 
         public ChunkKey (int _cx, int _cz)
         {
diff --git a/Substrate/SubstrateCS/Source/EntityCollection.cs b/Substrate/SubstrateCS/Source/EntityCollection.cs
index ab2b0e3..48bf1d2 100644
--- a/Substrate/SubstrateCS/Source/EntityCollection.cs
+++ b/Substrate/SubstrateCS/Source/EntityCollection.cs
@@ -150,14 +150,12 @@ namespace Substrate
 
         public class EntityEnumerator : IEnumerator<Entity>
         {
-            private TagList _entities;
             private IEnumerator<TagValue> _enum;
 
             private Entity _cur;
 
             public EntityEnumerator (TagList entities)
             {
-                _entities = entities;
                 _enum = entities.GetEnumerator();
             }
 
diff --git a/Substrate/SubstrateCS/Source/NBT/JSONSerializer.cs b/Substrate/SubstrateCS/Source/NBT/JSONSerializer.cs
index 6276f73..35f779b 100644
--- a/Substrate/SubstrateCS/Source/NBT/JSONSerializer.cs
+++ b/Substrate/SubstrateCS/Source/NBT/JSONSerializer.cs
@@ -109,7 +109,6 @@ namespace Substrate.NBT
 
         private static void SerializeScaler (TagValue tag, StringBuilder str)
         {
-            TagType type = tag.GetTagType();
             switch (tag.GetTagType()) {
                 case TagType.TAG_STRING:
                     str.Append("\"" + tag.ToTagString().Data + "\"");
diff --git a/Substrate/SubstrateCS/Source/NBT/NBT.cs b/Substrate/SubstrateCS/Source/NBT/NBT.cs
index 596b7c6..aac872e 100644
--- a/Substrate/SubstrateCS/Source/NBT/NBT.cs
+++ b/Substrate/SubstrateCS/Source/NBT/NBT.cs
@@ -279,7 +279,7 @@ namespace Substrate.NBT
         {
             TagType type = (TagType)_stream.ReadByte();
             if (type == TagType.TAG_COMPOUND) {
-                string name = ReadString().ToTagString().Data;
+                ReadString(); // name
                 return ReadValue(type) as TagCompound;
             }
 
diff --git a/Substrate/SubstrateCS/Substrate.csproj b/Substrate/SubstrateCS/Substrate.csproj
index 5dc035e..e618d2c 100644
--- a/Substrate/SubstrateCS/Substrate.csproj
+++ b/Substrate/SubstrateCS/Substrate.csproj
@@ -187,6 +187,9 @@
   <ItemGroup>
     <Folder Include="Source\Experimental\" />
   </ItemGroup>
+  <ItemGroup>
+    <None Include="Makefile" />
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.