How to investigate flow issues in waterways - Revision history

Frank@tygron.nl at 15:31, 30 January 2024

2024-01-30T15:31:23Z

← Older revision		Revision as of 15:31, 30 January 2024
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	* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to Water Areas only, check whether the location of the issue is covered by a [[water area (Water Overlay)\|Water Area]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|Limit Area]].		* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to Water Areas only, check whether the location of the issue is covered by a [[water area (Water Overlay)\|Water Area]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|Limit Area]].
	* Check whether the issue takes place near the the [[Edge effects (Water Overlay)\|edge of the calculation area]]. The closer to the edge a calculation takes place, the more chance there is of unintended [[Edge effects (Water Overlay)\|edge effects]].		* Check whether the issue takes place near the the [[Edge effects (Water Overlay)\|edge of the calculation area]]. The closer to the edge a calculation takes place, the more chance there is of unintended [[Edge effects (Water Overlay)\|edge effects]].

			[[Category:How-to's]]

Maxim@tygron.com at 16:11, 7 October 2022

2022-10-07T16:11:18Z

← Older revision		Revision as of 16:11, 7 October 2022
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	* Also check whether the height of the terrain is consistent, or inclined, and whether the height of the terrain exceeds the height of the water at any point.		* Also check whether the height of the terrain is consistent, or inclined, and whether the height of the terrain exceeds the height of the water at any point.

	===Is there a ~~Construction~~ in the waterway which causes a blockage?===		===Is there a Building in the waterway which causes a blockage?===
	* Activate the Water Overlay and see whether there is a [[Hydraulic structures (Water Overlay)\|~~Construction~~]] in that location. See if there is a [[Weir (Water Overlay)\|Weir]] or a [[pump (Water Overlay)\|Pump]] with an angle configured. You can tell by the dam visualized in that location. If so, inspect that ~~Construction~~ to see how and when water can flow past it, and how much.		* Activate the Water Overlay and see whether there is a [[Hydraulic structures (Water Overlay)\|Building]] in that location. See if there is a [[Weir (Water Overlay)\|Weir]] or a [[pump (Water Overlay)\|Pump]] with an angle configured. You can tell by the dam visualized in that location. If so, inspect that Building to see how and when water can flow past it, and how much.
	* Also see if there is an [[inlet (Water Overlay)\|Inlet]], [[pump (Water Overlay)\|Pump]], or [[sewer overflow (Water Overlay)\|Overflow]] in that location. It's possible water is added in that location and just flows off in one direction, or that in that location water is removed at such a rate that it doesn't reach the other side of the waterway.		* Also see if there is an [[inlet (Water Overlay)\|Inlet]], [[pump (Water Overlay)\|Pump]], or [[sewer overflow (Water Overlay)\|Overflow]] in that location. It's possible water is added in that location and just flows off in one direction, or that in that location water is removed at such a rate that it doesn't reach the other side of the waterway.

Frank@tygron.nl at 12:06, 28 May 2021

2021-05-28T12:06:25Z

← Older revision		Revision as of 12:06, 28 May 2021
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	===Is there an edge of the calculation model nearby?===		===Is there an edge of the calculation model nearby?===
	* Check what the current [[grid cell size]] is, and check whether the issue occurs near the edge of the project area. Note that the [[Border model (Water Overlay)\|outer two cells of the project area are not part of the calculation]].		* Check what the current [[grid cell size]] is, and check whether the issue occurs near the edge of the project area. Note that the [[Border model (Water Overlay)\|outer two cells of the project area are not part of the calculation]].
	* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to Water ~~Level~~ Areas only, check whether the location of the issue is covered by a [[water ~~level~~ area (Water Overlay)\|Water ~~Level~~ Area]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|Limit Area]].		* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to Water Areas only, check whether the location of the issue is covered by a [[water area (Water Overlay)\|Water Area]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|Limit Area]].
	* Check whether the issue takes place near the the [[Edge effects (Water Overlay)\|edge of the calculation area]]. The closer to the edge a calculation takes place, the more chance there is of unintended [[Edge effects (Water Overlay)\|edge effects]].		* Check whether the issue takes place near the the [[Edge effects (Water Overlay)\|edge of the calculation area]]. The closer to the edge a calculation takes place, the more chance there is of unintended [[Edge effects (Water Overlay)\|edge effects]].

Rudolf@tygron.nl: /* Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow? */

2020-06-12T08:53:15Z

Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?

← Older revision		Revision as of 08:53, 12 June 2020
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	===Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?===		===Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?===
	* Make sure you have both the general [[heightmap (Overlay)\|Heightmap Overlay]] and the [[Surface elevation result type (Water Overlay)\|surface elevation result type Overlay]] in your Project. Create a Measurement perpendicular across the waterway, and show both Overlays, one as primary and the other as base. Take note of whether the surface elevation Overlay's results match the depth of the Heightmap Overlay, and whether the incline at the sides matches up. If the incline is shallower, the [[grid cell size]] may be too high to allow for the intended steepness.		* Make sure you have both the general [[heightmap (Overlay)\|Heightmap Overlay]] and the [[Surface elevation result type (Water Overlay)\|surface elevation result type Overlay]] in your Project. Create a Measurement perpendicular across the waterway, and show both Overlays, one as primary and the other as base. Take note of whether the surface elevation Overlay's results match the depth of the Heightmap Overlay, and whether the incline at the sides matches up. If the incline is shallower, the [[grid cell size]] may be too high to allow for the intended steepness.
			* If the waterway is narrow, and not aligned to cardinal directions, it's possible a cell partially on one shore of the waterway is adjacent to a cell partially on the other shore of the waterway. In other words there is no cell which is entirely part of the waterway for water to flow through. The result is that the waterway is effectively blocked.

	===Is there a hydrological feature nearby which blocks the waterway?===		===Is there a hydrological feature nearby which blocks the waterway?===

Rudolf@tygron.nl at 13:25, 8 June 2020

2020-06-08T13:25:02Z

Rudolf@tygron.nl: /* Is there an edge of the calculation model nearby? */

2020-06-02T11:13:16Z

Is there an edge of the calculation model nearby?

← Older revision		Revision as of 11:13, 2 June 2020
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	* Check what the current [[grid cell size]] is, and check whether the issue occurs near the edge of the project area. Note that the [[Border model (Water Overlay)\|outer two cells of the project area are not part of the calculation]].		* Check what the current [[grid cell size]] is, and check whether the issue occurs near the edge of the project area. Note that the [[Border model (Water Overlay)\|outer two cells of the project area are not part of the calculation]].
	* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to water level areas only, check whether the location of the issue is covered by a [[water level area (Water Overlay)\|water level area]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|limit area]].		* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to water level areas only, check whether the location of the issue is covered by a [[water level area (Water Overlay)\|water level area]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|limit area]].
	* Check whether the issue takes place near the the edge of the calculation area. The closer to the edge a calculation takes place, the more chance there is of unintended edge effects.		* Check whether the issue takes place near the the [[Edge effects (Water Overlay)\|edge of the calculation area]]. The closer to the edge a calculation takes place, the more chance there is of unintended [[Edge effects (Water Overlay)\|edge effects]].

Rudolf@tygron.nl: /* Is there an edge of the calculation model nearby? */

2020-06-02T11:11:29Z

Is there an edge of the calculation model nearby?

← Older revision		Revision as of 11:11, 2 June 2020
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	===Is there an edge of the calculation model nearby?===		===Is there an edge of the calculation model nearby?===
	* Check what the current grid cell size is, and check whether the issue occurs near the edge of the project area. Note that the [[Border model (Water Overlay)\|outer two cells of the project area are not part of the calculation]].		* Check what the current [[grid cell size]] is, and check whether the issue occurs near the edge of the project area. Note that the [[Border model (Water Overlay)\|outer two cells of the project area are not part of the calculation]].
	* Check whether the location of the issue is inside the designated calculation area. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to water level areas only, check whether the location of the issue is covered by a water level area. If it is set to specified areas only, check whether the location of the issue is covered by a limit area.		* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to water level areas only, check whether the location of the issue is covered by a [[water level area (Water Overlay)\|water level area]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|limit area]].
	* Check whether the issue takes place near the the edge of the calculation area. The closer to the edge a calculation takes place, the more chance there is of unintended edge effects.		* Check whether the issue takes place near the the edge of the calculation area. The closer to the edge a calculation takes place, the more chance there is of unintended edge effects.

Rudolf@tygron.nl: /* Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow? */

2020-06-02T11:07:56Z

Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?

← Older revision		Revision as of 11:07, 2 June 2020
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	===Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?===		===Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?===
	* Make sure you have both the general [[heightmap (Overlay)\|heightmap overlay]] and the [[Surface elevation result type (Water Overlay)\|surface elevation]] overlay in your project. Create a measurement perpendicular across the waterway, and show both overlays, one as primary and the other as base. Take note of whether the surface elevation overlay's results match the depth of the heightmap, and whether the incline at the sides matches up.		* Make sure you have both the general [[heightmap (Overlay)\|heightmap overlay]] and the [[Surface elevation result type (Water Overlay)\|surface elevation]] overlay in your project. Create a measurement perpendicular across the waterway, and show both overlays, one as primary and the other as base. Take note of whether the surface elevation overlay's results match the depth of the heightmap, and whether the incline at the sides matches up. If the incline is shallower, the [[grid cell size]] may be too high to allow for the intended steepness.

	===Is there a hydrological feature nearby which blocks the waterway?===		===Is there a hydrological feature nearby which blocks the waterway?===

Rudolf@tygron.nl at 11:05, 2 June 2020

2020-06-02T11:05:14Z

← Older revision		Revision as of 11:05, 2 June 2020
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	===Is there a construction in the waterway which causes a blockage?===		===Is there a construction in the waterway which causes a blockage?===
	* Activate the water overlay and see whether there is a [[Hydraulic structures (Water Overlay)\|construction]] in that location. See if there is a [[Weir (Water Overlay)\|weir]] or a [[pump (Water Overlay)\|pump]] with an angle configured. You can tell by the dam visualized in that location. If so, inspect that construction to see how and when water can flow past it, and how much.		* Activate the water overlay and see whether there is a [[Hydraulic structures (Water Overlay)\|construction]] in that location. See if there is a [[Weir (Water Overlay)\|weir]] or a [[pump (Water Overlay)\|pump]] with an angle configured. You can tell by the dam visualized in that location. If so, inspect that construction to see how and when water can flow past it, and how much.
	* Also see if there is an inlet, pump, or overflow in that location. It's possible water is added in that location and just flows off in one direction, or that in that location water is removed at such a rate that it doesn't reach the other side of the waterway.		* Also see if there is an [[inlet (Water Overlay)\|inlet]], [[pump (Water Overlay)\|pump]], or [[sewer overflow (Water Overlay)\|overflow]] in that location. It's possible water is added in that location and just flows off in one direction, or that in that location water is removed at such a rate that it doesn't reach the other side of the waterway.

	===Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?===		===Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?===
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	===Is there a hydrological feature nearby which blocks the waterway?===		===Is there a hydrological feature nearby which blocks the waterway?===
	* If available, use the [[Base types result type (Water Overlay)\|base types result type]] to inspect the location and see whether cells are marked as breach, or as outside of calculation area, or otherwise inconsistently with the rest of the waterway.		* If available, use the [[Base types result type (Water Overlay)\|base types result type]] to inspect the location and see whether cells are marked as breach, or as outside of calculation area, or otherwise inconsistently with the rest of the waterway.
	* If the base types result type is not available, check whether there is a breach in the indicated location. You can do so by opening the water overlay's configuration wizard, open the step concerning "breaches", and check the locations of the breaches there (if any).		* If the base types result type is not available, check whether there is a [[breach (Water Overlay)\|breach]] in the indicated location. You can do so by opening the [[Water Overlay Wizard\|water overlay's configuration wizard]], open the step concerning "breaches", and check the locations of the breaches there (if any).

	===Is there an edge of the calculation model nearby?===		===Is there an edge of the calculation model nearby?===

Rudolf@tygron.nl: /* Is there a construction in the waterway which causes a blockage? */

2020-06-02T10:59:02Z

Is there a construction in the waterway which causes a blockage?

← Older revision		Revision as of 10:59, 2 June 2020
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	===Is there a construction in the waterway which causes a blockage?===		===Is there a construction in the waterway which causes a blockage?===
	* Activate the water overlay and see whether there is a [[~~hydraulic structure~~ (Water Overlay)\|construction]] in that location. See if there is a [[Weir (Water Overlay)\|weir]] or a [[pump (Water Overlay)\|pump]] with an angle configured. You can tell by the dam visualized in that location. If so, inspect that construction to see how and when water can flow past it, and how much.		* Activate the water overlay and see whether there is a [[Hydraulic structures (Water Overlay)\|construction]] in that location. See if there is a [[Weir (Water Overlay)\|weir]] or a [[pump (Water Overlay)\|pump]] with an angle configured. You can tell by the dam visualized in that location. If so, inspect that construction to see how and when water can flow past it, and how much.
	* Also see if there is an inlet, pump, or overflow in that location. It's possible water is added in that location and just flows off in one direction, or that in that location water is removed at such a rate that it doesn't reach the other side of the waterway.		* Also see if there is an inlet, pump, or overflow in that location. It's possible water is added in that location and just flows off in one direction, or that in that location water is removed at such a rate that it doesn't reach the other side of the waterway.

← Older revision		Revision as of 13:25, 8 June 2020
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	When using the [[Water Overlay]], water should usually be able to flow freely through waterways. For some situations, it may be evident that water should not be able to flow further, such as at a properly configured ~~weir~~ or ~~pump~~, or when the bottom of the waterway rises or has an obvious bump.		When using the [[Water Overlay]], water should usually be able to flow freely through waterways. For some situations, it may be evident that water should not be able to flow further, such as at a properly configured [[Weir (Water Overlay)\|Weir]] or [[Pump (Water Overlay)\|Pump]], or when the bottom of the waterway rises or has an obvious bump.

	==How to check whether water flows properly==		==How to check whether water flows properly==
	You may be able to see visually on the ~~overlay~~ where potential issues exist, but by placing a ~~measurement~~ in the waterway you will be able to see more accurately how much water is where in the waterway.		You may be able to see visually on the Overlay where potential issues exist, but by placing a Measurement in the waterway you will be able to see more accurately how much water is where in the waterway.
	{{howto\|title=check whether water flows properly through a waterway		{{howto\|title=check whether water flows properly through a waterway
	\| Ensure the Water Overlay has a [[Surface last value result type (Water Overlay)\|surface last value]] result type and a [[surface elevation result type (Water Overlay)\|surface elevation]].		\| Ensure the Water Overlay has a [[Surface last value result type (Water Overlay)\|surface last value]] result type and a [[surface elevation result type (Water Overlay)\|surface elevation]].
	\| Open the [[~~measuring~~ tool]].		\| Open the [[Measuring tool]].
	\| Create a line ~~measurement~~, with one endpoint at the start of the waterway, and the other endpoint at the end of the waterway.		\| Create a line Measurement, with one endpoint at the start of the waterway, and the other endpoint at the end of the waterway.
	\| Set the primary ~~overlay~~ to surface last value, the base overlay to surface elevation, and activate "sum".		\| Set the primary Overlay to surface last value, the base overlay to surface elevation, and activate "sum".
	\| Set the ~~measurement~~ graph display mode to "fit to graph".		\| Set the Measurement graph display mode to "fit to graph".
	\| You now see the water level across the length of the waterway.		\| You now see the water level across the length of the waterway.
	}}		}}
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	Because inhibited waterflow can have a number of causes, there isn't a single fix for all situations. Check whether any of the following apply to your situation, and interpret in the context of your own use-case what the desirable solution would be.		Because inhibited waterflow can have a number of causes, there isn't a single fix for all situations. Check whether any of the following apply to your situation, and interpret in the context of your own use-case what the desirable solution would be.
	===Is the surface elevation in that location what you expect?===		===Is the surface elevation in that location what you expect?===
	* In the relevant waterway, use the ~~measurement~~ made earlier to see whether the height of the bottom of the waterway is as shallow or as deep as you expect.		* In the relevant waterway, use the Measurement made earlier to see whether the height of the bottom of the waterway is as shallow or as deep as you expect.
	* Also check whether the height of the terrain is consistent, or inclined, and whether the height of the terrain exceeds the height of the water at any point.		* Also check whether the height of the terrain is consistent, or inclined, and whether the height of the terrain exceeds the height of the water at any point.

	===Is there a ~~construction~~ in the waterway which causes a blockage?===		===Is there a Construction in the waterway which causes a blockage?===
	* Activate the ~~water overlay~~ and see whether there is a [[Hydraulic structures (Water Overlay)\|~~construction~~]] in that location. See if there is a [[Weir (Water Overlay)\|~~weir~~]] or a [[pump (Water Overlay)\|~~pump~~]] with an angle configured. You can tell by the dam visualized in that location. If so, inspect that ~~construction~~ to see how and when water can flow past it, and how much.		* Activate the Water Overlay and see whether there is a [[Hydraulic structures (Water Overlay)\|Construction]] in that location. See if there is a [[Weir (Water Overlay)\|Weir]] or a [[pump (Water Overlay)\|Pump]] with an angle configured. You can tell by the dam visualized in that location. If so, inspect that Construction to see how and when water can flow past it, and how much.
	* Also see if there is an [[inlet (Water Overlay)\|~~inlet~~]], [[pump (Water Overlay)\|~~pump~~]], or [[sewer overflow (Water Overlay)\|~~overflow~~]] in that location. It's possible water is added in that location and just flows off in one direction, or that in that location water is removed at such a rate that it doesn't reach the other side of the waterway.		* Also see if there is an [[inlet (Water Overlay)\|Inlet]], [[pump (Water Overlay)\|Pump]], or [[sewer overflow (Water Overlay)\|Overflow]] in that location. It's possible water is added in that location and just flows off in one direction, or that in that location water is removed at such a rate that it doesn't reach the other side of the waterway.

	===Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?===		===Is the grid cell size so large that the sides of the waterway are recomputed to be more shallow?===
	* Make sure you have both the general [[heightmap (Overlay)\|~~heightmap overlay~~]] and the [[Surface elevation result type (Water Overlay)\|surface elevation]] ~~overlay~~ in your ~~project~~. Create a ~~measurement~~ perpendicular across the waterway, and show both ~~overlays~~, one as primary and the other as base. Take note of whether the surface elevation ~~overlay~~'s results match the depth of the ~~heightmap~~, and whether the incline at the sides matches up. If the incline is shallower, the [[grid cell size]] may be too high to allow for the intended steepness.		* Make sure you have both the general [[heightmap (Overlay)\|Heightmap Overlay]] and the [[Surface elevation result type (Water Overlay)\|surface elevation result type Overlay]] in your Project. Create a Measurement perpendicular across the waterway, and show both Overlays, one as primary and the other as base. Take note of whether the surface elevation Overlay's results match the depth of the Heightmap Overlay, and whether the incline at the sides matches up. If the incline is shallower, the [[grid cell size]] may be too high to allow for the intended steepness.

	===Is there a hydrological feature nearby which blocks the waterway?===		===Is there a hydrological feature nearby which blocks the waterway?===
	* If available, use the [[Base types result type (Water Overlay)\|base types result type]] to inspect the location and see whether cells are marked as ~~breach~~, or as outside of calculation area, or otherwise inconsistently with the rest of the waterway.		* If available, use the [[Base types result type (Water Overlay)\|base types result type Overlay]] to inspect the location and see whether cells are marked as [[Breach (Water Overlay)\|Breach]], or as outside of calculation area, or otherwise inconsistently with the rest of the waterway.
	* If the base types result type is not available, check whether there is a [[breach (Water Overlay)\|~~breach~~]] in the indicated location. You can do so by opening the [[Water Overlay Wizard\|~~water overlay~~'s configuration wizard]], open the step concerning "~~breaches~~", and check the locations of the ~~breaches~~ there (if any).		* If the base types result type is not available, check whether there is a [[breach (Water Overlay)\|Breach]] in the indicated location. You can do so by opening the [[Water Overlay Wizard\|Water Overlay's configuration wizard]], open the step concerning "Breaches", and check the locations of the Breaches there (if any).

	===Is there an edge of the calculation model nearby?===		===Is there an edge of the calculation model nearby?===
	* Check what the current [[grid cell size]] is, and check whether the issue occurs near the edge of the project area. Note that the [[Border model (Water Overlay)\|outer two cells of the project area are not part of the calculation]].		* Check what the current [[grid cell size]] is, and check whether the issue occurs near the edge of the project area. Note that the [[Border model (Water Overlay)\|outer two cells of the project area are not part of the calculation]].
	* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to ~~water level areas~~ only, check whether the location of the issue is covered by a [[water level area (Water Overlay)\|~~water level area~~]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|~~limit area~~]].		* Check whether the location of the issue is inside the designated [[Limit rain (Water Overlay)\|calculation area]]. You can do so at the weather event step in the configuration wizard, where you can check the configuration for the calculation area. If it is set to Water Level Areas only, check whether the location of the issue is covered by a [[water level area (Water Overlay)\|Water Level Area]]. If it is set to specified areas only, check whether the location of the issue is covered by a [[limit area (Water Overlay)\|Limit Area]].
	* Check whether the issue takes place near the the [[Edge effects (Water Overlay)\|edge of the calculation area]]. The closer to the edge a calculation takes place, the more chance there is of unintended [[Edge effects (Water Overlay)\|edge effects]].		* Check whether the issue takes place near the the [[Edge effects (Water Overlay)\|edge of the calculation area]]. The closer to the edge a calculation takes place, the more chance there is of unintended [[Edge effects (Water Overlay)\|edge effects]].