# SDR results at different resolutions

**URL:** <https://community.naturalcapitalalliance.org/t/sdr-results-at-different-resolutions/6190>\
**Category:** Science, Research & Data\
**Tags:** sdr\
**Created:** [September 8, 2025, 2:52pm UTC](https://community.naturalcapitalalliance.org/t/sdr-results-at-different-resolutions/6190 "2025-09-08T14:52:16Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![jesseG](https://yyz1.discourse-cdn.com/flex031/user_avatar/community.naturalcapitalalliance.org/jesseg/32/1068_2.png) [@jesseG](https://community.naturalcapitalalliance.org/u/jesseG)\
**Post date:** [September 8, 2025, 5:19pm UTC](https://community.naturalcapitalalliance.org/t/sdr-results-at-different-resolutions/6190/2 "2025-09-08T17:19:36Z")

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Hi @BrynZA ,

Welcome! Please read and understand [the User Guide](https://storage.googleapis.com/releases.naturalcapitalproject.org/invest-userguide/latest/en/index.html) before using InVEST. Then, search this forum for answers to your questions before posting new ones. Related posted include these:

- [RouteDEM issues; DEM artifacts](https://community.naturalcapitalalliance.org/t/routedem-issues-dem-artifacts/4685)
- [SDR：the study area contains basins](https://community.naturalcapitalalliance.org/t/sdr-the-study-area-contains-basins/5811) .

Varying the DEM between 30m and 90m resolution versions without changing the threshold flow accumulation (TFA) value will drastically impact export estimates. As [stated in the User Guide](https://storage.googleapis.com/releases.naturalcapitalproject.org/invest-userguide/latest/en/sdr.html#data-needs), TFA

> directly affects the expression of hydrologic connectivity and the sediment export result: when a flow path reaches the stream, sediment trapping stops and the sediment exported is assumed to reach the catchment outlet. It is important to choose this value carefully, so modeled streams come as close to reality as possible.

Also be sure to read about [TFA](https://storage.googleapis.com/releases.naturalcapitalproject.org/invest-userguide/latest/en/data_sources.html#tfa) and the [DEM](https://storage.googleapis.com/releases.naturalcapitalproject.org/invest-userguide/latest/en/getting_started.html#working-with-the-dem).

Have you compared and validated your modeled stream networks with real-world stream maps or imagery?

-Jesse

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_[View the full topic](https://community.naturalcapitalalliance.org/t/sdr-results-at-different-resolutions/6190)._