Challenges to Sewering in Northern Stockholm County

Norrtälje, Sweden

The Norrtälje Municipality, encompassing the top third of Northern Stockholm County, presents a unique infrastructure challenge. With a permanent population of approximately 65,000 residents, the area experiences a dramatic seasonal surge of up to 180,000 inhabitants during the summer months. This tripling in population is driven by the presence of more than 30,000 summer homes – the highest concentration in all of Sweden.

Challenge:

The region’s popularity as a summer destination has created a need for robust and scalable wastewater collection solutions, but the existing infrastructure is not equipped to handle the seasonal influx. The Swedish government has mandated Paragraph 6, the replacement of outdated septic systems with municipal centralized sewer systems. However, the implementation of these updates proved complex and faced public resistance.

• Topography & Geology: The area is extremely rocky and requires blasting, making the deep trenching excavation both technically difficult and costly, while introducing significant safety risks.
• Existing Development: The communities and homes are already established, making  traditional gravity-based sewer systems significantly more costly and disruptive.
• Public Sentiment: Some residents did oppose the municipal system buildout and had reluctancy to pay for infrastructure perceived as unnecessary, despite its environmental and public health advantages.

Solution:

To overcome these challenges, the municipality adopted E/One’s pressure sewer system as the most viable and cost-effective solution given the terrain, seasonal influx, and existing residential structures.

• Minimal Disruption: Installation is minimally invasive and efficient, avoiding large-scale excavation.
• Long-Term Reliability: E/One grinder pumps are purpose-built and require no preventive maintenance, often going a decade or more between service calls.
• Environmental Impact: This pressure sewer system is built to last, ensuring clean water and wastewater for generations to come.