Tromsø
tromso.kommune.noManaging excessive saline water inflow and infiltration (I&I) in coastal regions poses a perpetual challenge for water utilities. Tromsø stands as a prime example grappling with this reality. Being placed north on the Norwegian West coast, the region faces a unique convergence of geographical factors, contending not only with substantial spring floods from mountainous terrains but also coping with the influence of the Gulf Stream, maintaining a climate hovering around freezing temperatures, compounded by a significant tidal range of 4 meters.
This unique environmental setting exposes Tromsø's coastal wastewater pumping stations to the threat of saline water inundation during high tides. The resulting corrosive impact leads to significant economic damage to infrastructure, necessitating costly renovations. This process also causes an economic and environmental loss as the pump stations transport seawater to Tromsø's wastewater plants, leading to the unnecessary expenditure of energy to treat substantial volumes of already "clean" seawater. While the ideal scenario involves a water system impermeable to saline I&I water, Tromsø has pioneered a proactive strategy to mitigate the challenges posed by I&I.
What sets Tromsø's approach apart is its divergence from seeking the outright elimination of excess saline water. Instead, the focus is on enabling targeted isolation of saline I&I influx at specific stations through strategic shutdowns of pumps. By preventing saline water from traveling further in the system and corroding the pipes, this method significantly mitigates infrastructure damage.
However, implementing such a strategy requires a sophisticated system capable of collecting and integrating data from pumping stations, weather forecasts, and tidal ranges, and transforming this data into user-friendly analyses. To achieve this, Tromsø initiated a collaborative partnership with Smartvatten. This collaboration aims to develop and implement an adaptive smart system that provides an encompassing overview and visualization of their entire network.
The system has helped us see clearly in an analytical way the state of the sewage network and pumping stations - Tromsø municipality
Smartvatten Neuro is a data analytic service for water utilities and operates by collecting pump runtime, flow measurement, energy data, weather forecasts, and tidal ranges through APIs directly into the interface. The system performs calculations and transforms data into adaptive analyses crucial for making strategic data-driven decisions throughout the organization. It maps and locates the impact of I&I water in the system by monitoring weather data and sea levels in combination with the actual flow in the pumping stations. The data is presented visually through pie charts, diagrams, direct numbers and a map view. Facilitating a comprehensive understanding of the type and volume of water flowing through each station. Additionally, the system triggers alarms in case of deviations in the flow at any pumping station, aiding in the swift location of inflows or blockages. The system is built with an iterative approach, which has resulted in an adaptable system that can easily be extended into other areas within water management.
Through our comprehensive study of pumping stations predominantly impacted by saline water influx, we've unveiled a significant revelation: saline water constitutes a staggering 70% of total water volume within these stations at the height of high tides. Implementing a strategic shutdown of these stations during peak periods promises a dual benefit. Firstly, it will substantially reduce the presence of saline water within the system. Secondly, it will lead to a remarkable 60% reduction in weekly energy consumption at the identified stations. Moreover, this action will cascade into additional energy savings across other stations, which no longer need to pump excess water through the system.
Blue line: represents the tidal range. The yellow line: actual energy usage in this specific pumping station. Green line: The calculated energy usage in a dry weather flow – what the energy usage would look like if the station wasn’t impacted by saline water.
Blue line: represents the tidal range during a peak high tide. Yellow line: is the actual flow in this specific pumping station. Green line: Calculated dry weather flow – what the flow would look like if it wasn’t impacted by saline water.
