The Blockade System Explained

[PhilThib]

In CW2, the blockade of the Confederacy is handled via different types of actions and factors, as follows:

The Factors

• Blue Water blockade: Union naval units inside the blockade boxes (Atlantic and Gulf) will contribute to increasing the % of blockade. There is a diminishing return on investment as it will be harder and harder to increase this % once you are past 30 to 40%. For that you need Brown Water Blockade.
• Brown Water Blockade: Union naval units and Union control of key coastal forts will blockade directly the adjacent port(s). For instance, Fort Monroe will blockade all CSA ports on the James River, and ships in Charleston Bay will blockade this port directly.
• Key Confederate Ports: some key ports, if unblockaded, will reduce the Union blockade efficiency (due to their high level of blockade runners activity, kept higher if unblockaded).

All of this will generate an overall blockade percentage which will give the final percentage (blockade % divided by 2) of production lost in all CSA ports. This percentage can never be lower than 0% (despite modifications) or higher than 50% (if you manage to have 100% Blockade %, but this is almost impossible). This will affect all the ports’ production (WSU, Supplies, Ammos, Money, not conscripts). That the harbors are not blockaded don’t change anything here, they are hampered by the global situation.

[color="#0000FF"]What are the key figures then?[/color]

Union Naval Units blockade values.
They contribute to the blue water blockade via their blockade values. For brown blockade, the value is indifferent, as long as it enough to blockade the port (see icon on map in such a case).
On average, Union Blockade flotillas are valued at 67 blockade points, which trough a set of complex formulas will net something between 5 and 7% of blockade, before reduction for non blockaded harbors. But the more you shall add flotillas, the less efficient they shall be.

Blockaded Harbors
Those harbors blockaded via naval units (or forts) will add a certain percentage of blockade, as follows:

Region / (Harbor name) : / Blockade %

James City, VA (Hampton Roads) : 1
Richmond ,VA (Richmond) : 1
Norfolk, VA (Norfolk) : 5
Warwick, VA (Suffolk) : 1

Currituck, NC (Edenton) : 1
Tyrell, NC (Plymouth) : 1
Hyde, NC (Swan Quarter) 1
Beaufort, NC (New Bern): 3
Carteret, NC (Beaufort) : 3
New Hanover, NC (Wilmington) : 8

Georgetown, SC (Georgetown) : 1
Charleston, SC (Charleston) : 8
Jasper, SC (Hardee's Station) : 1
Beaufort, SC (Beaufort) : 1

Ebert, GA (Augusta) : 1
Chatham, GA (Savannah) : 6
Pullman, GA (Jacksonville) : 1
Wayne, GA (Brunswick) : 1
Calhoun, GA (St. Mary) : 1

Franklin, FL (Appalachicola) : 1
Leon, FL (Tallahassee) : 1
Duval, FL (Jacksonville) : 1
Levy, FL (Waccasassa) : 1
Saint John, FL (St. Augustine) : 1
Volusia, FL (New Smyrna) : 1
Hillsboro, FL (Tampa) : 1
Escambia, FL (Pensacola) : 3

Mobile, AL (Mobile) : 5

Gulf, MS (Mississippi City) : 1

Iberville, LA (New Orleans) : 16
St Joseph, LA (St. Joseph) : 1
Alexandria, LA (Alexandria) : 1
Pierre, LA (Plaquemine) : 1
Berwick, LA (Berwick) : 1
Baton Rouge, LA (Baton Rouge) : 1

Beaumont, TX (Beaumont) : 1
Galveston, TX (Galveston) : 5
Matagorda, TX (Matagorda) : 7
Cameron, TX (Brownsville) : 2
Kleberg, TX (King Ranch) : 1
Nueces, TX (Corpus Christi) : 1
Jackson, TX (Indianola) : 1


Non Blockaded Harbors
Those harbors that are NOT blockaded via naval units (or forts) will remove a certain percentage of the accumulated blockade (to a maximum of -16% if all are left unblockaded), as follows:

Region / (Harbor name) : / Blockade %

Norfolk, VA (Norfolk) : [color="#FF0000"]-2[/color]

New Hanover, NC (Wilmington) : [color="#FF0000"]-2[/color]

Charleston, SC (Charleston) :[color="#FF0000"] -3[/color]

Chatham, GA (Savannah) : [color="#FF0000"]-1[/color]

Escambia, FL (Pensacola) : [color="#FF0000"]-1[/color]

Mobile, AL (Mobile) :[color="#FF0000"] -1[/color]

Iberville, LA (New Orleans) : [color="#FF0000"]-5[/color]

Matagorda, TX (Matagorda) : [color="#FF0000"]-1[/color]

[aaminoff]

This is amazingly useful information.

Looking at the unit tooltips, I see that Blockade Ships (which you can only get inside a Blockade Squadron) have a Blockade Value of 10 - which is why 6 of them + a few more from the other two ships = 67. Brigs on the other hand have a Blockade Value of 2, so they are only useful in Brown Water.

Union control of key coastal forts will blockade directly the adjacent port(s). For instance, Fort Monroe will blockade all CSA ports on the James River, and ships in Charleston Bay will blockade this port directly.

Is this really true? Even though there is no "port blockaded" icon next to all those ports?

I always thought that forts were not useful in and of themselves for blockading, they served as convenient places to park your blockading forces to recover cohesion and in many spots if they were enemy owned they would shoot your blockading forces as they moved in. But then one time I took Ft James, TX, and was surprised to see a "port blockaded" icon appear by Galveston, even though I had no ships in Galveston's harbor's sea zone.

So do all forts blockade the ports inland of them, but the icon does not appear? Or conversely is the bug simply that the link between forts and harbors they blockade is not in place for many (most) forts?

For completeness and clarity, I believe it is also separately the case that a fort projects 4 elements worth of blockade into their immediately adjacent sea zone. This is why for example the tooltip for Hampton Roads says it requires only 4 elements to blockade not 8. But that is not what I am talking about here.

[Mickey3D]

I'm just discovering this thread now : thanks, this is really useful information

[aaminoff]

Browsing the data folders, I found a file called USADistantBlockades, which does indeed seem to define ports that are blockaded by specific "distant" forts being enemy controlled. I started a new April 61 campaign as CSA using 1.02 and in fact I see "harbor being blockaded by enemy ships or forts" icons on Richmond, James City, and Norfolk, and in the file we see

SelectFaction = USA
SelectRegion = $Ft_Monroe_VA
StartEvent = USA_DistantBlockade_FtMonroe|999|0|NULL|NULL|$Ft_Monroe_VA|NULL

Conditions

EvalRgnOwned = $Ft_Monroe_VA

Actions
SetDistantBlockades = $Ft_Monroe_VA;$Richmond_VA;$Ft_Monroe_VA;$James_City_VA;$Ft_Monroe_VA;$Norfolk_VA

EndEvent

City Point, Prince Georges and Suffolk, Warwick do not have the icon and are missing from the list above. That is likely an oversight.

I also speculate that the reason I almost never saw the blockade icons before is that quite often they are hidden behind enemy forces that you can not move. So basically you have to trust that they are there.

In conclusion, a campaign of coastal fort siegeing can be pretty effective for the USA. Most forts will blockade the confederate harbors upstream. And since they are easily resupplied by sea, besieging them is quite tough for the CSA.

[Ace]

But what if the fort is tore down by CSA. I see the game checks for region ownership, not for having a fort and guns in the fort?

Similar question, if the US takes New Orleans without taking the forts, why can't the forts blockade US in New Orleans. I see the event only working if the US holds the forts. It is not fair.

[aaminoff]

I would hazard a guess that it only applies to the CSA because a port being blockaded in this way is only relevant for blockade percentage purposes, not for any other use of the port. Which is still a bug, but there it is. I think I read in another thread somewhere someone complaining that they were besieging New Orleans and had all the forts but NO was still getting supply.

This is actually even sort of correct. If side A owns New Orleans and side B owns the forts at the mouth of the Mississippi, NO is blockaded as a port for purposes of trading with Europe, but as a harbor on the Mississippi river it could still draw supply from upstream. Perhaps having rules to figure out the blocked state of a given port for different purposes is too difficult, or at any rate was not done in the current code.

[marquo]

"• Brown Water Blockade: Union naval units and Union control of key coastal forts will blockade directly the adjacent port(s). For instance, Fort Monroe will blockade all CSA ports on the James River, and ships in Charleston Bay will blockade this port directly."

This may not be working; I captured Fort Fisher and Fort Caswell; but Wilmington and Southport did not become blockaded (with the blockade icon) until I placed enough ships in the harbors.

[Q-Ball]

"• Brown Water Blockade: Union naval units and Union control of key coastal forts will blockade directly the adjacent port(s). For instance, Fort Monroe will blockade all CSA ports on the James River, and ships in Charleston Bay will blockade this port directly."

This may not be working; I captured Fort Fisher and Fort Caswell; but Wilmington and Southport did not become blockaded (with the blockade icon) until I placed enough ships in the harbors.

I have found the graphic doesn't always work, even if the port is blockaded

Also, make sure you have artillery units in the forts; if they were destroyed, they won't blockade the harbor

[Ebbingford]

I have found the graphic doesn't always work, even if the port is blockaded

The graphic for a blockaded port doesn't show when you first load a game, when you process a turn it appears.

[rattler01]

Please sticky this thread.

[PhilThib]

Please sticky this thread.

Done

[pgr]

A quick question on Charleston. How do enemy held forts effect the number of ships needed to blockade the port? In charleston bay (just outside the 3 forts) the tool tip indicates I need 12 ships, but even with 32 neither the port nor the forts are shown as blockaded. I'm assuming each enemy fort increases the number of ships needed?

[Ace]

You have to be right next to Charleston, or hold the FtSumter in order to blockade it effectively.

[pgr]

Ace, to be clear then, I have to either hold Sumter or be next to Charleston, between the city and her forts? Thanks for the clarification!

[elxaime]

What would be nice is a keystroke that would allow you to see what is blockaded, as the icon isn't visible always. Something along the lines of holding down a a key+shift and all the blockaded ports/regions will blink.

Also - as far as artillery needing to be in a fort for the blockade effect to occur, does anyone know how much artillery? Does it need to be coastal guns? Or will six pounders work?

[Merlin]

I've never used a 6lb. battery to make it happen, but I do knowf for a fact as long as you have at least a 12lb. battery in the fort and there are no Confederate ships in the coastal region in question, the blockade works with just the fort. Conversely, you can blockade a port by having at least the number of elements shown in the tool-tip in the harbor exit region, regardless of the number of batteries in any other Confederate forts bordering that region. Thus it's actually possible to blockade Charleston with a naval force sufficiently powerful enough to satisfy the requirements even if you control none of the forts, though I wouldn't recommend it as the cost to enter will be painful.

[Godagesil]

But what if the fort is tore down by CSA. I see the game checks for region ownership, not for having a fort and guns in the fort?

Similar question, if the US takes New Orleans without taking the forts, why can't the forts blockade US in New Orleans. I see the event only working if the US holds the forts. It is not fair.

Historically the Union sailed up the river and captured the city bypassing the forts and captured New Orleans. The Confederate troops then had to abandon the forts down stream because their lines of supply and been severed. You need to visit Louisiana and the lower Mississippi delta to appreciate the terrain, which is in itself quite the foe. Swamps and bayous, virtually impossible to operate in. It explains why the Confederacy never made a serious attempt to try and recapture the city.

[Ubercat]

Historically the Union sailed up the river and captured the city bypassing the forts and captured New Orleans. The Confederate troops then had to abandon the forts down stream because their lines of supply and been severed. You need to visit Louisiana and the lower Mississippi delta to appreciate the terrain, which is in itself quite the foe. Swamps and bayous, virtually impossible to operate in. It explains why the Confederacy never made a serious attempt to try and recapture the city.

Would the same thing occur in game? A Union force which captures NO after merely running the guns would then be cut off. Assuming a lot of supply wagons were sent along to maintain the force for a good length of time, would the forts wither away into ineffectiveness or continue to block supplies indefinitely?

[Captain_Orso]

Would the same thing occur in game?

No. We could not find a reasonable mechanism for forts to surrender without being besieged from on land.

A Union force which captures NO after merely running the guns would then be cut off.

"Cut off" from what? Supply? The navy carries their own supplies with them. They can carry enough to last for months, but in this case I'm sure it wasn't that much. Besides, once Farragut took NO, NO itself was full of supplies.

Assuming a lot of supply wagons were sent along to maintain the force for a good length of time,

Not supply trains, transports, the ones the troops arrived on.

would the forts wither away into ineffectiveness or continue to block supplies indefinitely?

I don't know what you are trying to express here with "wither away". I expect that the forts will have plenty of supply on hand to last far longer that you would want to wait for the garrison to use it up. Besiege and assault the forts and have it over with and then move on with the game is the best way to do it.

[Ubercat]

......Not supply trains, transports, the ones the troops arrived on.

Thanks for the pretty comprehensive response. Are you saying here that the invasion fleet loads up unused shipping capacity with extra supplies for its invasion force? That would be great, and a good reason to send a lot of extra transports.

[Captain_Orso]

Dood, take a transport squadron, which has a capacity of 20, load weight 20 worth of troops onto it and check how much GS and Ammo it is then carrying.

Check how much supply your force needs per turn. Then you can calculate out how much supply you need to take with you.

[BigDuke66]

SelectFaction = USA
SelectRegion = $Ft_Monroe_VA
StartEvent = USA_DistantBlockade_FtMonroe|999|0|NULL|NULL|$Ft_M onroe_VA|NULL

Conditions

EvalRgnOwned = $Ft_Monroe_VA

Actions
SetDistantBlockades = $Ft_Monroe_VA;$Richmond_VA;$Ft_Monroe_VA;$James_Ci ty_VA;$Ft_Monroe_VA;$Norfolk_VA

EndEvent

So this means even when I got Ft. Monroe I'm only blocking Richmond, James City & Norfolk but not Suffolk and City Point?
Can I block Suffolk and City Point at all? I already have a blockade fleet at Hampton Roads

Besides this with the missing icons I'm totally unsure how to blockade certain ports, New Orleans seems the most important, how to block it?
Would it be enough to block the regions "Koney Island" and "South Mississippi Delta"?

What about Wilmington?
I'm already blocking Reaves Point and by this block Ft. Caswell & Fisher

What about Charleston?
I'm already blocking Charleston Bay with 14 elements and don't see any blockade Icon.

[pgr]

All of this will generate an overall blockade percentage which will give the final percentage (blockade % divided by 2) of production lost in all CSA ports. This percentage can never be lower than 0% (despite modifications) or higher than 50% (if you manage to have 100% Blockade %, but this is almost impossible). This will affect all the ports’ production (WSU, Supplies, Ammos, Money, not conscripts). That the harbors are not blockaded don’t change anything here, they are hampered by the global situation.

A tardy question on an old post. Does the blockade effect all structures in the port town, or just the port itself? Take Richmond. Is the iron works impacted in addition to the port, or is it just the production of the port structure in Richmond that is impacted?

[Captain_Orso]

From what I've seen, every structure producing any kind of income is affected.

[pgr]

From what I've seen, every structure producing any kind of income is affected.

So it pays to close blockade Richmond eh?

[Pocus]

it's more based on the type of the output than the nature of the structure. From memory, blockade don't have any effect on conscripts production.

[GraniteStater]

From what I've seen, every structure producing any kind of income is affected.

So it pays to close blockade Richmond eh?

Not to beat an old horse too much, but this is what I was saying six months ago. If one would rather forego the Blue Tsunami strategy and pursue HiTek Union, then why not go for a robust Blockade? While the Union is buying all the toys and eschewing umpteen Brigades upon Brigades, why let the CSA cash checks? Might as well cut into his income, the central idea being, when you do hit 'em with good Leaders with Eng/Med/Pontoon/Signal (mostly so they can stay when they take ground and, if playing with Replacements Only at Depots, can stay and Replace), they won't be able to respond or counterattack with the alacrity they might wish.

[chocko101]

Hi everyone! I just purchased this game as well as the DLC expansion and this is my first post. I'm trying to figure out blockades and read through the posts I could find on the is forum.

I'm trying to sort out if I've actually blockaded a port. In a scenario I'm playing I'm trying to blockade the ports of Plymouth, NC and Edenton NC. My blockading force is located at Albemarle Sound.. The tool tip for Albemarle Sound says I need "to have at least 4 naval elements to blockade this zone". Currently my blockade force consists of 2x navy units. Each navy unit contains two elements (brigs), with each element worth 2 blockade factors. So by my count I have a total of 4 elements worth 8 blockade factors. I've had this force in place for a few turns and I do not see any indicator that the blockade is in fact working.

On a side note, is there a way to access the overall effectiveness of the blockade if I'm playing the AI?

[Cardinal Ape]

Hi everyone! I just purchased this game as well as the DLC expansion and this is my first post. I'm trying to figure out blockades and read through the posts I could find on the is forum.

I'm trying to sort out if I've actually blockaded a port. In a scenario I'm playing I'm trying to blockade the ports of Plymouth, NC and Edenton NC. My blockading force is located at Albemarle Sound.. The tool tip for Albemarle Sound says I need "to have at least 4 naval elements to blockade this zone". Currently my blockade force consists of 2x navy units. Each navy unit contains two elements (brigs), with each element worth 2 blockade factors. So by my count I have a total of 4 elements worth 8 blockade factors. I've had this force in place for a few turns and I do not see any indicator that the blockade is in fact working.

On a side note, is there a way to access the overall effectiveness of the blockade if I'm playing the AI?

Hello and welcome to the forums, chocko101.

You will need a total of 8 ship elements to blockade those ports. Since you already have 4 ships there the tool-tip tells you need 4 (more) ships. If you flip your 4 ships into passive posture and check the tool-tip it should jump back up to 8.

I'm not sure what you mean by, 'with each element worth 2 blockade factors' -- All warships are only worth one blockade element a piece.

The standard to blockade a port is 8 ships, but if the enemy has entrenched artillery defending the port then you will need 12 ships. You can counter with your own land based artillery to decrease it by 4.

For telling how much damage your blockade is doing here is a page with some number breakdowns.

Aside from increasing the blockade % in the boxes you may want to send your ships to brown blockade the larger industrial cities of the south, like New Orleans or Charleston.

[principes romanes]

Welcome again to the forum chocko!

I believe that the blockade factors you are referring to is the 'Blockade' value listed under the 'Various' tab when you look at the details of a naval unit. When a ship is adjacent to a port and blockading it directly (Brown Water Blockading), the game just counts the number of (war) ships. When a ship is in one of the blockade boxes, it is the 'Blockade' value that applies. Essentially this means that blockade ships (which can only be built in blockade flotillas) are much, much better than other ships in the blockade boxes.

Once you have a port blockaded, you should see a little icon appear on the map. It can sometimes be hidden under units though.

If you are playing against the AI (or yourself), another way to check that a blockade is working is to load the turn as the CSA and open the ledger tab (F8) to see how much $, CS, and WS a city is producing. Savannah and Wilmington usually have pretty similar production so if you can blockade one of them that can give you a sense of how much the blockade is doing.