Stormwater solutions
Makes it easy
We work as stormwater specialists at StormTac. We also develop and sell the stormwater and recipient model StormTac Web.
The model has hundreds of users in companies, municipalities and universities and is a tool for calculations of stormwater flows and design of measures for flow detention and treatment of stormwater pollutants. The model can also be used to calculate the effects of pollutants on watercourses, lakes and seas and the required treatment for these receiving waters.
Latest News
- Updated method for calculating acceptable pollutant load to the recipient 22 Apr , 2025
- May 6, Requirements for Stormwater effluent concentration criteria with regard to EQS – webinar 03 Apr , 2025
- Export with consideration of upstream flow detention – new automation with improved functions 15 Jan , 2025
- Treatment Guidelines for stormwater with regard to EQS 30 Sep , 2024
Why StormTac?
StormTac corporation has an extensive experience of projects concerning stormwater and impacts on receiving waters. The experience includes both preliminary studies (investigations) and detailed design projects of stormwater treatment, transport and flow detention facilities, calculations of pollutant loads with stormwater and baseflow, development of GIS-stormwater models in the form of stormwater action plans for municipalities and environment effect evaluations.


All in one solution
StormTac Web is unique since it in one single model includes the interactions within the whole watershed system, runoff and base flow – pollutant transport – receiving water impacts and criteria – design of transport, pollutant treatment and flow detention facilities.
Easy to use
The tool is user-friendly and self explanatory. It consists of an overview flowchart with clickable input data boxes, the results are presented in the flowchart.
Notes and a quick manual describes the simple steps from start to end of calculations. You can begin directly without any required education.

StormTac Database
StormTac Database compiles e.g unique annual flow-weighted data calculated by e.g. NURP, NSQD and the BMP database, as well as from other literature data. The data is updated continuously (weekly/monthly) with new data from more substances, land uses and treatment facilities.
The data is implemented in the stormwater and receiving water application StormTac Web with default recommended typical values that can be changed by the user to reflect site-specific conditions.
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70 |
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Substances in database | Substances in StormTac Web | Different land uses | Treatment facilities |