Everything about N-OF09 Overflow Test (Burrow Protection)
id;activity_name;activity_type;activity_descriptor;breaching;animal;erosion;temporary;levee_survey;prolonged;start_date;end_date;date_length_day;date_length_hour;date_other;levee_stretch;location_x;location_y;location_z;location_descriptor;location_other;objectif_important;objectif_knowledge;pre_condition;act_des;monitoring_process;monitoring_reasoning;limits;during_activity;post_activity;activity_result;results_conc;knowledge_desc;ref_links;wrk_1;wrk_2;wrk_3;key_info
73;N-OF09 Overflow Test (Burrow Protection);Other;"The NL-OF09 overflow test section is characterized by a series of small (mice) burrows. It is know from previous tests that the presence of burrows may compromise the strength of the levee cover and invoke collapse if contact exists between the outside of the levee and the sand core, in which situation the outflow of sand through burrows may lead to collapse of the levee cover.
In order to prevent such process from occurring, a burrow protection mechanism has been devised, consisting of plastic plates that are anchored to the surface and to promote water to flow over the plates, and thus preventing from significant amounts of water to enter the levee surface layer (and sand core).
The test has been closely monitored by ERT measurements in the test section, as well as visual descriptions.";False;True;True;True;False;False;;;;10.0;11 blocks of overflow activity.;VI;51.34808;4.22948;12.0;;"Lambert '72 coordinates:
X=140295.8 m; 
Y= 226487.0 m.";Investigate the possibility to protect burrows from impact of overflow.;Understand erosion processes related to small burrows in the levee slope.;Prior to the test, the section did not appear to have any noticeable discontinuities, such as damage by machinery, irregular vegetation patterns or large animal burrows. Through a thorough visual inspection before commencement of the test a number of small burrows were detected within and adjacent to the test section. Their depths were in the range of 8-12 cm and their diameters in the range of 3-5 cm, while none of them seemed to have penetrated beyond the cover layer. Their geometry and spatial distribution resembled mice burrows.;10 hours of overflow at 500 L/s.m.;- Overhead cameras (4) - Acoustic water height sensors - Electromagnetic current velocity sensors - Discharge sensor (EM or acoustic);"Description of the hydraulic conditions of the overflow. The setup is described in Vercruysse et al. (2022): ""Design and application of an overflow generator."" (Ref WL2022R20_047_1)";;During the test, surface erosion and burrows were monitored every 2 blocks. Surface erosion started with the uprooting of grass and exposure of small patches of clay with diameters in the order of 2-3 cm, which gradually expanded and connected with adjacent patches of clay. This is a common pattern that has been observed in all overflow tests in the living lab. Most of the mice burrows in the test section were within the first patches that formed, which shows that the burrows may have played a role in the early formation of surface erosion. Similar observations in other overflow tests are needed to validate this finding.;After the test, the most significant damages could be observed at the transition between EPDM and bare soil on the crest (erosion depth 1-2 cm in an area approx. 20 x 80 cm), at the toe (erosion depth 5-10 cm in an area approx. 10 x 80 cm) and at the downstream transition between asphalt and soil (erosion depth 45-50 cm in an area approx. 30 x 30 cm).;;"Factual data report:
https://stowanl-my.sharepoint.com/:w:/g/personal/llhpp_stowa_nl/EX5yYnuJ-EBBjoKAxAwg8LkBef8ra9V_-GHjzbkz0Was8g?e=pyaUSq

Factual data report annexes:
https://stowanl-my.sharepoint.com/:w:/g/personal/llhpp_stowa_nl/EWIzoxIhxopCryc6744YgHYBBWr_0fhoGpJ_1pSy0_tM2w?e=pY8Hc6

An integration report:
Will be added later.";An integration report will be added later (February 2023) as knowledge document.;under development;True;False;False;


All DATA concerning N-OF09 Overflow Test (Burrow Protection)
data_type;data_descripion;date_date;data_find;data_media;data_media_find
Sensor timeseries, pictures, ...;;;https://stowanl-my.sharepoint.com/:f:/g/personal/llhpp_stowa_nl/El2o2p5nvDlEgZ8ImYG6sUUBdARdQK8gXy4SGNklzWoiKA?e=gfyyA3;;


All EQUIPMENTS concerning N-OF09 Overflow Test (Burrow Protection)
equip_type;equip_usage
"Overflow generator.
";"The setup is described in Vercruysse et al. (2022): ""Design and application of an overflow generator."" (Ref WL2022R20_047_1)"


All SENSORS concerning N-OF09 Overflow Test (Burrow Protection)
No sensors added