diff --git a/GeneralsMD/Code/GameEngine/Source/GameLogic/Map/TerrainLogic.cpp b/GeneralsMD/Code/GameEngine/Source/GameLogic/Map/TerrainLogic.cpp
index f2173b15e4b..845226f3f80 100644
--- a/GeneralsMD/Code/GameEngine/Source/GameLogic/Map/TerrainLogic.cpp
+++ b/GeneralsMD/Code/GameEngine/Source/GameLogic/Map/TerrainLogic.cpp
@@ -2668,7 +2668,7 @@ void TerrainLogic::flattenTerrain(Object *obj)
 			Real totalHeight = 0;
 			Int numSamples = 0;
 			for (i=iMin.x; i<=iMax.x; i++) {
-				for (j=0; j<=iMax.y; j++) {
+				for (j=MAX(0, iMin.y); j<=iMax.y; ++j) {
 					Vector3	testPt(i*MAP_XY_FACTOR, j*MAP_XY_FACTOR, 0);
 					Bool match = false;
 					unsigned char flags;
@@ -2694,7 +2694,7 @@ void TerrainLogic::flattenTerrain(Object *obj)
 			if (rawDataHeight>centerHeight) rawDataHeight = centerHeight;
 
 			for (i=iMin.x; i<=iMax.x; i++) {
-				for (j=0; j<=iMax.y; j++) {
+				for (j=MAX(0, iMin.y); j<=iMax.y; ++j) {
 					Vector3	testPt(i*MAP_XY_FACTOR, j*MAP_XY_FACTOR, 0);
 					Bool match = false;
 					unsigned char flags;
@@ -2759,7 +2759,7 @@ void TerrainLogic::flattenTerrain(Object *obj)
 			Real totalHeight = 0;
 			Int numSamples = 0;
 			for (i=iMin.x; i<=iMax.x; i++) {
-				for (j=0; j<=iMax.y; j++) {
+				for (j=MAX(0, iMin.y); j<=iMax.y; ++j) {
 					Vector3	testPt(i*MAP_XY_FACTOR, j*MAP_XY_FACTOR, 0);
 					Bool match = false;
 					Real dx = testPt.X - pos->x;
@@ -2777,7 +2777,7 @@ void TerrainLogic::flattenTerrain(Object *obj)
 			Real avgHeight = totalHeight/numSamples;
 			Int rawDataHeight = REAL_TO_INT_FLOOR(0.5f + avgHeight/MAP_HEIGHT_SCALE);
 			for (i=iMin.x; i<=iMax.x; i++) {
-				for (j=0; j<=iMax.y; j++) {
+				for (j=MAX(0, iMin.y); j<=iMax.y; ++j) {
 					Vector3	testPt(i*MAP_XY_FACTOR, j*MAP_XY_FACTOR, 0);
 					Bool match = false;
 					Real dx = testPt.X - pos->x;
@@ -2854,7 +2854,7 @@ void TerrainLogic::createCraterInTerrain(Object *obj)
 
 	for (Int i = iMin.x; i <= iMax.x; i++ )
   {
-		for ( Int j=0; j <= iMax.y; j++ )
+		for ( Int j=MAX( 0, iMin.y ); j <= iMax.y; ++j )
     {
 			deltaX = ( i * MAP_XY_FACTOR ) - pos->x;
 			deltaY = ( j * MAP_XY_FACTOR ) - pos->y;