Firstly, consider including keywords related to your main business focus: "smart", "water", "resources", "monitoring" and "scheduling". Examples could include SmartWaterMonitoring.com or WaterSchedulingTech.com.

Secondly, incorporate AI-related terms such as "Artificial Intelligence", "Intelligence" or "AI-driven". Examples can be AIForSmartWater.com or IntelligentWaterManagement.com.

Thirdly, consider adding words that signify security like "Secure" or "Protected". For example, SecureWaterManagement.ai or ProtectedWaterResources.com.

Lastly, urban planning and design can be represented by terms like "Urban", "City", "Planning", or "Design". Some examples could be UrbanWaterManagement.ai or CityWaterSolutions.com.

Always ensure the chosen domain name is unique, easy to remember, and resonates with your brand values and mission. It should also not violate any trademarks or copyrights.

In terms of security, you may want to choose a reliable domain registrar and hosting service provider who can guarantee the safety and privacy of your online data. In addition, it’s advisable to use HTTPS protocol for added security.