Water Tower Design and Performance: Grimes Enterprise Drive

Have you ever driven through a city, a small rural town, or a sprawling industrial complex and noticed a massive, towering structure silhouetted against the sky? Beyond community landmarks or canvases for town City logos and identity, Water towers, are essential to maintaining reliable drinking water systems. The City of Grimes, Iowa, demonstrates how a water tower can support growing communities by improving system operations, maintaining pressure, and planning for long-term demand.

During construction, The August 2020 Midwest derecho damaged the tower’s steel tank while it was being welded at grade, prior to being raised. The response required:

• A comprehensive structural assessment of the damaged sections of the Water Tower
• Development of a repair and reinforcement strategy
• Coordination with the contractor to ensure compliance will design requirements and specifications

This process highlights the importance of resilient infrastructure design, which includes both construction-phase and long-term operational and environmental risks.

Why Are Water Towers Built High? The Physics of Flow and Pressure

If you have ever asked yourself, “why are water tanks built high?”, the answer comes down to the fundamental force in our universe: gravity.

Elevation is the critical factor in maintaining consistent system pressure without relying solely on mechanical pumping in Water Tower design, including the Grimes Enterprise Drive project. By storing water above ground, the water distribution system relies on gravitational force to distribute water efficiently across the system with sufficient pressure across all demand scenarios.

Water is usually pumped into elevated towers during lower demand periods (off-peak hours), which allows the distribution system to store potential energy. When demands increase, the potential energy is utilized to maintain flow and pressure without immediate reliance on high-powered pumps that are costly to operate. To ensure water reaches customers with sufficient pressure, engineers rely on hydraulic head calculations. For every foot of elevation water is stored above ground level, 0.433 pounds per square inch (PSI) of pressure is gained.

The Grimes Enterprise Drive Water Tower was designed to provide at least 50 psi of pressure across the growing service area, supporting both daily usage and emergency fire protection needs. Proper elevation ensures consistent operation and service during peak demand periods and reduces strain on pumps.

When evaluating storage options, engineers often compare ground storage and elevated storage alternatives. While a ground storage reservoir (GSR) offer benefits including lower construction costs and ease of maintenance, a Water Tower provides unique advantages, particularly in flat terrain conditions like Grimes and much of the Midwest United States.

Benefits of a Water Tower:

• Provides consistent system pressure by gravity
• Reduces reliance on real-time pumping
• Minimizes land footprint in growing service areas
• Improves system reliability during peak demand

The City of Grimes, in partnership with Central Iowa Water Works (CIWW), separately constructed a 2 MG GSR co-located at the Water Treatment Plant site in 2025. The GSR project was designed to provide additional finished water storage to comply with regulatory standards, provides capacity for the high-service pumping station to deliver large volumes of water during peak demands, and decouples the simultaneous need to produce large volumes of treated water, which is operationally challenging and energy intensive.

The Enterprise Drive Water Tower works in tandem with the GSR and high-service pump station to create a hybrid system to balance finished water storage capacity and operational efficiency. This operational approach allows the water system to:

• Maintain consistent pressure across the entire distribution network
• Provide reliable fire protection capacity across the entire distribution network
• Balance storage with pumping operation, improving energy efficiency
• Respond effectively to fluctuations in demands

Together, these coordinated system components ensure the Water Tower functions as a key part of the larger, integrated water system.

The Grimes Enterprise Drive Water Tower represents more than just a landmark, it is a critical investment in water system reliability, efficiency, and future growth potential.

By combining thoughtful design, coordinated integration with related assets, and resilient engineering, the project demonstrates how water towers can support growing communities while maintaining consistent service and performance.

As water demands continue to grow across the Midwest, projects like this highlight the importance of designing infrastructure that not only meets today’s needs, but is future-ready.