Iowa

Iowa Storm Water Management Manual

StateIowahighNeeds review

This extraction needs human review.

The listed software are noted in the text as 'typical modeling programs' rather than explicitly 'required'. Version and last revised dates were not explicitly distinguished beyond the general publication date of October 28, 2009.

Fields not found in document: document_metadata.version_or_edition, document_metadata.last_revised_date

Document Metadata

Jurisdiction level

state

“Iowa Storm Water Management Manual”
Chapter 1- Section 1, Page 1 of 8

State

Iowa

“The Nationwide Permit Program Fact Sheet No. 7 (IA)”
Chapter 1- Section 3, Page 5 of 10

Version / edition

Not found in document

No evidence cited

Adoption / effective date

2009-10-28

“October 28, 2009”
Chapter 1- Section 1, Page 1 of 8

Last revised date

Not found in document

No evidence cited

Relationship to state manual

independent

“Iowa Storm Water Management Manual”
Chapter 1- Section 1, Page 1 of 8

Design Criteria

Design storm return periods (years)

1-year, 2-year, 5-year, 10-year, 25-year, 50-year, 100-year

“the 1-year, 24-hour storm... 5-year recurrence interval... 2-year and 10-year... 25-year... 50-year (Qp50)... 100-year, 24-hour storm event”
Chapter 1- Section 4, Pages 3-4 of 7

Water quality volume method

Equivalent to the rainfall depth in inches (using the recommended 90% cumulative frequency depth of 1.25 inches) multiplied by the volumetric runoff coefficient (Rv) for the site and the site drainage area.

“In numerical terms, it is equivalent to the rainfall depth in inches (the 90% cumulative frequency rainfall depth) multiplied by the volumetric runoff coefficient (Rv) for the site, and the site drainage area.”
Chapter 1- Section 4, Page 2 of 7

Peak flow calculation method(s)

Rational Method, WinTR-55 Method, TR-20 Model, HEC-1, HEC-HMS, Regression equations

“Use the Rational Method for drainage areas up to 160 acres... Use the WinTR-55 Method for drainage areas up to 2000 acres... TR-20 Model... Routines contained in HEC-1 or HEC-HMS computer models... Regression equations”
Chapter 1- Section 5, Page 2 of 8

Required hydrologic/hydraulic software

HEC-RAS, HEC-2, SWMM, WSPRO, HY-8, WinTR-55, HEC-1, HEC-HMS, TR-20

“HEC-RAS - river analysis systems... HEC-2 - water surface profiles... SWMM - stormwater management model... WSPRO - water surface profiles... HY-8 - hydraulic design of highway culverts”
Chapter 1- Section 5, Page 4 of 8

Approved BMP categories

Non-structural BMPs, Stormwater Detention BMPs, Infiltration BMPs, Vegetative BMPs

“Non-structural BMPs... Stormwater Detention BMPs... Infiltration BMPs... Vegetative BMPs”
Chapter 1- Section 3, Page 8 of 10