{"id":102202,"date":"2026-07-21T15:31:26","date_gmt":"2026-07-21T15:31:26","guid":{"rendered":"https:\/\/geostru.ai\/en\/products\/hid\/"},"modified":"2026-07-21T15:33:53","modified_gmt":"2026-07-21T15:33:53","slug":"hid","status":"publish","type":"page","link":"https:\/\/geostru.ai\/en\/products\/hid\/","title":{"rendered":"HID NX"},"content":{"rendered":"
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HID NX<\/h1>\n<\/div><\/div>\n\n

Web-based hydraulic invariance design \u2014 sizing of stormwater attenuation systems so that a development does not increase the peak discharge to the receiving water. Five methods computed side by side, regulatory profiles for Italy and abroad, and an AI assistant that sets up a project from a plain-language description. Opens in any browser \u2014 no installs, no hardware keys.<\/p>\n<\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n

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HID NX - web-based hydraulic invariance design, sizing methods and storage checks<\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n
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What it does<\/h2>\n<\/div><\/div>\n\n

Five sizing methods side by side<\/strong> \u2014 minimum requirements, rain-only, direct method, time of concentration and the detailed procedure, computed together with the governing storage volume always in view.<\/p>\n<\/div><\/div>\n\n

Drainage areas and runoff<\/strong> \u2014 each surface with its area and runoff coefficient, with the weighted \u03c6 and the impervious-equivalent area recomputed as you type.<\/p>\n<\/div><\/div>\n\n

Rainfall curves<\/strong> \u2014 GEV or two-parameter depth-duration-frequency curves, with a separate sub-hourly exponent and the 28 standard durations tabulated and plotted.<\/p>\n<\/div><\/div>\n\n

Design storms and losses<\/strong> \u2014 Chicago, uniform, Sifalda and triangular hyetographs, with percentage, Horton or SCS-CN rainfall losses computed per surface.<\/p>\n<\/div><\/div>\n\n

Hydrographs and routing<\/strong> \u2014 time-of-concentration and Nash models, routed through the storage step by step against the real outlet law, not a constant discharge assumption.<\/p>\n<\/div><\/div>\n\n

Eight outlet devices<\/strong> \u2014 constant discharge, Thomson, Bazin and Crump weirs, submerged orifice, sluice gate, constant infiltration and infiltration wells.<\/p>\n<\/div><\/div>\n\n

Regulatory profiles<\/strong> \u2014 Lombardia (R.R. 2017, 2019 and 2025), Emilia-Romagna and Marche, plus a generic international profile. The app shows only the fields the selected rules actually require.<\/p>\n<\/div><\/div>\n\n

AI assistant<\/strong> \u2014 set up a whole project from a plain-language description, and get every input and result explained in context.<\/p>\n<\/div><\/div>\n\n

Reports and cloud save<\/strong> \u2014 the calculation report is generated natively in Word (DOCX), DOC and PDF, in seven languages, with cloud project save on GeoDropbox.<\/p>\n<\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n

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How it works<\/h2>\n<\/div><\/div>\n\n

A guided flow takes you from the drainage areas to a fully verified, reported attenuation design.<\/p>\n<\/div><\/div>\n\n

1 \u00b7 Areas & methods<\/strong> \u2014 enter the drainage surfaces with their runoff coefficients, then pick the sizing methods you want compared.<\/p>\n<\/div><\/div>\n\n

2 \u00b7 Rainfall curve<\/strong> \u2014 enter the GEV or two-parameter coefficients and the return period, and check the depth-duration curve.<\/p>\n<\/div><\/div>\n\n

3 \u00b7 Hydrology & losses<\/strong> \u2014 curve number, time of concentration and specific storage per surface, then the design storm and the loss model.<\/p>\n<\/div><\/div>\n\n

4 \u00b7 Storage & outlet<\/strong> \u2014 set the storage area and design head, choose the outlet device, then run the calculation.<\/p>\n<\/div><\/div>\n\n

5 \u00b7 Checks<\/strong> \u2014 read the governing storage volume, the required height and the drain-down time against your design values.<\/p>\n<\/div><\/div>\n\n

6 \u00b7 Report & save<\/strong> \u2014 generate the report in Word (DOCX), DOC or PDF in seven languages, and save the project to GeoDropbox.<\/p>\n<\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n

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Who it's for<\/h2>\n<\/div><\/div>\n\n

Hydraulic engineers \u00b7 Civil engineers \u00b7 Geologists \u00b7 Land-development designers. HID NX is built for those who today must attach a hydraulic invariance report to a building permit, a masterplan or a discharge authorization.<\/p>\n<\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n

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Frequently asked questions<\/h2>\n<\/div><\/div>\n\n

What does HID calculate?<\/strong>Five methods run together, so you read the governing storage volume at a glance: minimum requirements, rain-only, direct method, time of concentration and the detailed procedure \u2014 the last one a step-by-step simulation of the design storm, the losses, the hydrograph and the routing through the storage.<\/p>\n<\/div><\/div>\n\n

Can the AI assistant set up the project for me?<\/strong>Yes. It builds the project from a plain-language description \u2014 surfaces, runoff coefficients, rainfall curve and outlet \u2014 and explains every input and result in context.<\/p>\n<\/div><\/div>\n\n

What languages does the report support?<\/strong>Seven \u2014 Italian, English, German, French, Romanian, Spanish and Polish. The language you pick in the toolbar applies to the report too, not just the interface.<\/p>\n<\/div><\/div>\n\n

Which regulations does it cover?<\/strong>Lombardia (R.R. 7\/2017 with the 2019 and 2025 updates), Emilia-Romagna and Marche, each with its own required inputs, allowed methods and prescribed discharge limit. Everywhere else a generic international profile lets you set the discharge limit and the minimum volume yourself.<\/p>\n<\/div><\/div>\n\n

Can I use it outside Italy?<\/strong>Yes. The hydrological engine is universal; only the regulatory layer is country-specific. Pick the generic profile, enter your own rainfall coefficients and the discharge limit set by your local authority, and the app works the same way.<\/p>\n<\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n

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Ready to start with HID NX?<\/h2>\n<\/div><\/div>\n\n

Choose your plan and start using HID NX today. Runs in the browser, always up to date, no installation required.<\/p>\n<\/div><\/div>\n\n\n\n\n<\/div>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"

Web-based hydraulic invariance design \u2014 sizing of stormwater attenuation systems to five methods, with regulatory profiles for Italy and abroad and an AI assistant. Browser-based, no installs.<\/p>\n","protected":false},"author":0,"featured_media":0,"parent":101181,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_ai_seo_pilot_schema_type":"auto","footnotes":""},"class_list":["post-102202","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/geostru.ai\/en\/wp-json\/wp\/v2\/pages\/102202","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/geostru.ai\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/geostru.ai\/en\/wp-json\/wp\/v2\/types\/page"}],"replies":[{"embeddable":true,"href":"https:\/\/geostru.ai\/en\/wp-json\/wp\/v2\/comments?post=102202"}],"version-history":[{"count":2,"href":"https:\/\/geostru.ai\/en\/wp-json\/wp\/v2\/pages\/102202\/revisions"}],"predecessor-version":[{"id":102205,"href":"https:\/\/geostru.ai\/en\/wp-json\/wp\/v2\/pages\/102202\/revisions\/102205"}],"up":[{"embeddable":true,"href":"https:\/\/geostru.ai\/en\/wp-json\/wp\/v2\/pages\/101181"}],"wp:attachment":[{"href":"https:\/\/geostru.ai\/en\/wp-json\/wp\/v2\/media?parent=102202"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}