Whisk water, soy sauce, sugar, and lime juice together in small bowl until sugar is dissolved; set aside. Bring 2 quarts water to boil in large saucepan. Add noodles and cook, stirring often, until nearly tender. Drain noodles and rinse thoroughly with cold water; set aside.
Heat 1 teaspoon oil in 12-inch nonstick skillet over medium heat until shimmering. Add bell pepper and carrot and cook, stirring frequently, until crisp-tender, about 2 minutes; transfer to bowl, cover with aluminum foil, and set aside until ready to serve.
Add remaining 1 tablespoon oil, curry powder, garlic, and ginger to now-empty skillet and cook over medium heat until fragrant, 15 to 30 seconds. Add soy sauce mixture and noodles, tossing to coat noodles with sauce, and cook until liquid is absorbed but noodles are still glossy, 1 to 2 minutes. Season with salt and pepper to taste. Divide among individual serving bowls, then top with vegetable mixture and shrimp and sprinkle with cilantro and scallions. Serve with lime wedges.