Skyrim Special Edition version available here

This mod simply tries to make swimming feel more immersive and somewhat realistic, without adding much too deep or complex mechanisms.
It is geared towards simplicity and maximum compatibility, while preserving the much-needed features for a more immersive and somewhat realistic swimming experience.
It doesn't meant to make swimming to be completely realistic, due to the game limitations, balance reason, simplicity sake, and such.


FEATURES

• Encumbered swimming (ie. the weight of your equipped gears make you swim slower).
• Compatible with other mods which modify swimming speed (uses actor value modifier instead of direct edit to the swimming speed records).
• Swimming costs Stamina and you will drown (take damage) when you are out of Stamina (automatically disabled when Vigor, Wildcat, Smilodon, or YASH2 is installed).
• Replaces vanilla breath-timing drowning mechanism with Stamina-based drowning mechanism (ie. the more Stamina you have, the longer you can swim without drowning).
• Having Waterbreathing effects (spells, enchantments, potions, etc) or being an Argonian exempt you out from the drowning damage.
• No changes to race records, NPC records, or Waterbreathing magic effect records (compatible with race overhaul mods and mods which edit NPCs/magic effects/etc).
• Has proper description in the active effects section for the encumbered swimming and drowning effect (you will know what's happening with your character).
• Extremely lightweight scripting (no continuously running funtions, no complex calculation, take very little to none resources to run).
• Also works to all NPCs as long as they have ActorTypeNPC keyword (NPCs take no drowning damage for balance reason, but they still take Stamina damage).
  

Encumbered Swimming
The weight of your equipped gears will slow you down when swimming. This does it in a simple way, which is explained below:

• Any equipped Two-handed weapons will slow your movement speed by 5% when swimming.
• Any equipped Shield (either Light or Heavy armor, makes no difference) wll slow your movement speed by 10% when swimming. Shields slow more due to their general shape (ie. board-like) which is somewhat prone to block the flow of water when swimming, especially if you are swimming in a non-linear way (either going down, going up, moving right, or moving left).
• Any equipped Clothing (in any body parts, as long as it's keyworded with any "Clothing" keyword) or Helmets or Gauntlets or Boots (either Light or Heavy armor, makes no difference) will slow your movement speed by 5% when swimming.
• Any equipped Light Cuirass (ie. torso part of the body) will slow your movement speed by 10% when swimming.
• Any equipped Heavy Cuirass will slow your movement speed by 20% when swimming.
  

They stack to each other, so equipping some or all of them together will accumulate the swimming speed slowdown. The actual weight of each of the gear doesn't matter. What matters is the category they belong to, which is Two-handed weapon, or Shield, or Clothing/Helmet/Gauntlet/Boot, or Light Cuirass, or Heavy Cuirass. This is to make it simple and intuitive, yet still somewhat realistic, which works out of the box for all mod-added gears without potentially causing compatibility or balance problems in the gameplay level. This feature works for both PC and NPCs (as long as they have ActorTypeNPC keyword).

Stamina-based Drowning Mechanism
This mod replaces the vanilla game's breath-timing drowning mechanism (ie. you will drown after being underwater for a specific amount of time) with Stamina-based drowning mechanism, in which you will drown after running out of Stamina. In other words, the more Stamina you have, the longer you can swim without drowning. This makes swimming feel more immersive, in a sense that your swimming capability will continue to improve along with the growth of your character (ie. the increase in Stamina). A newbie's swimming capability will be different with a veteran's.

The drowning is not actually "drowning" (ie. your character will not actually sink to the bottom of the water), unlike some other mods which did this already. I don't want to make it complicated, so the drowning is simply simulated by a continuous Health damage. Means than upon running out of Stamina, your Health will continuously decrease and obviously you will die in the end if you can't restore your Stamina back in time. If you are under a Waterbreathing effect, the drowning will simply cease. If you are an Argonian, you will not be drowned.

In addition, this mod also makes swimming cost Stamina. I know that there are mods which do this already, so i made the mod to automatically detect whether any of these mods are installed or not in your load order. If it is, then the Stamina consumption from this mod will be disabled to avoid having double or even multiple Stamina consumptions when swimming to run simultaneously. Currently, only 4 mods are supported: Vigor, Wildcat, Smilodon, and YASH2.

The Stamina consumption feature works for both PC and NPCs, but the drowning feature only works for PC for balance reason (because NPCs are not smart enough to keep themselves from dying in water).

Simple and Compatible
This mod was designed to be simple and compatible, by making as less edits to vanilla records as possible, and employing the most compatible methods to implement the features without potentially causing compatibility problems when being used along with other mods which have similar or overlapping features. The scripting was also done as simple as possible, by only writing the codes in the scripts which couldn't be implemented without scripting (ie. non-scripting methods were prioritized than scripting methods). The codes are clean, very lightweight, and won't cause any scripting issue. That said, interaction with other mods can still potentially give unpredictable result, especially for mods which are overly complicated and difficult to predict (which can also possibly due to the non-compatible methods they employ, or the problematic methods used by the authors of the said mods).


INSTALLATION
Put this mod below mods which edit the game settings fActorSwimBreathDamage and fActorSwimBreathBase in your load order (open all your installed plugins in xEdit to check for it).


COMPATIBILITY
The only vanilla records edited by this mod is the game settings fActorSwimBreathDamage and fActorSwimBreathBase. Any mods modifying these records will be conflicting (the one put at the bottom of the load order will win). Other than these, this mod makes no changes to other records. No changes to race records, NPC records or Waterbreathing magic effect records, making this mod fully compatible with other mods which edit such records out of the box.

This mod makes changes to an actor's swimming speed (ie. the actor's movement speed when swimming) using actor value modifier which make it stack with whatever other edits to the actor's movement speed by other mods, thus improving compatibility. Of course, the end result will vary depends on what mods modifying the same actor value in your load order.

This mod also takes into account if you have Vigor, Wildcat, Smilodon, or YASH2 installed in your load order. The Stamina consumption when swimming will be automatically disabled, allowing these mods to apply their own Stamina consumption on swimming. No patch needed.


CREDITS

• Nitor for his Better Swimming mod and jonharwood for his Drowning mod which serve as the framework of this mod
  

MY OTHER LE MODS
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