STORM WATER COMPLIANCE
CONSTRUCTION PRACTICE SOLUTION
TESTED QUESTIONS AND ANSWERS
COMPLETE SUCCESS KIT
●● A pond meets peak flow but has no water quality feature. Is it
compliant?
Answer: No
●● A pipe system meets flow but HGL exceeds ground. What is the
issue?
Answer: Flooding risk
●● A BMP is designed but no maintenance agreement is recorded. Is it
compliant?
Answer: No
●● A site exceeds 50% improvement threshold. What classification
applies?
Answer: New development
●● A pond lacks emergency spillway. What risk exists?
Answer: Overtopping failure
,●● An infiltration BMP is placed in high groundwater. What happens?
Answer: It fails or is noncompliant
●● A system has low velocities. What issue occurs?
Answer: Sediment buildup
●● A system has excessive velocity. What issue occurs?
Answer: Erosion
●● A design matches peak flow but ignores volume. What is missing?
Answer: Water quality compliance
●● What conditions make a project "redevelopment" under Section 3.5?
Answer: It is development on a previously developed site where
impervious surface exceeds 20 percent of the total site and
improvements to the subject property exceed 50 percent of the total site
value.
●● What activities are expressly included within "redevelopment" for
Section 3.5 purposes?
Answer: Remodeling of existing building interiors, resurfacing of paved
areas, and exterior building changes are included.
,●● What activities are expressly excluded from "redevelopment"?
Answer: Ordinary maintenance activities that do not increase or
concentrate stormwater runoff or cause additional nonpoint source
pollution are excluded.
●● To what area do Section 3.5 redevelopment requirements apply?
Answer: They apply to the entire parcel in question, but do not apply to
parcel areas less than 1 acre or sites with a greater than 80 percent
existing building footprint that is not being removed.
●● What are the three alternative redevelopment performance standards
in Section 3.5.1?
Answer: (1) Reduce impervious cover on the site by at least 20 percent;
or (2) achieve a 10 percent reduction in the 24-hour runoff volume from
the 50 percent AEP storm while confirming post-development peak
discharge does not exceed pre-development for that storm; or (3) reduce
post-development peak discharge rates by 10 percent of existing peak
discharge rates for the 10 percent and 4 percent AEP storms while
confirming the 24-hour post-development volume does not exceed pre-
development volume for those storms.
●● What special note applies if permeable pavers are used only to
satisfy the 20 percent impervious cover reduction option?
, Answer: If they meet the material and construction requirements of the
LID guide, they do not require infiltration or Seasonal High Water Table
testing.
●● For non-special protection areas, when may the redevelopment
performance standards in Section 3.5.1 be bypassed?
Answer: Only if adequate downstream storm drainage conveyance
capacity all the way to receiving waters can be demonstrated.
●● For special protection areas, how do redevelopment standards
interact with other requirements?
Answer: One of the redevelopment requirements must still be applied, in
addition to the requirements in Sections 3.9.3 and 3.6.
●● What are the two redevelopment exemptions listed in Section 3.5.2?
Answer: (1) Construction or improvement of an SFR, except for SFR in
a special protection area adding 500 square feet or more of impervious
area; and (2) minor land-disturbing activities that do not disturb more
than 0.5 acres, are not part of an LCP, are not in a special protection
area, and do not increase post-development impervious area by greater
than 10 percent of the impervious area at the time of CAA submittal.
●● What approval condition applies to redevelopment exemptions?
Answer: They must be documented for City approval as stated in
Section 4.10.
CONSTRUCTION PRACTICE SOLUTION
TESTED QUESTIONS AND ANSWERS
COMPLETE SUCCESS KIT
●● A pond meets peak flow but has no water quality feature. Is it
compliant?
Answer: No
●● A pipe system meets flow but HGL exceeds ground. What is the
issue?
Answer: Flooding risk
●● A BMP is designed but no maintenance agreement is recorded. Is it
compliant?
Answer: No
●● A site exceeds 50% improvement threshold. What classification
applies?
Answer: New development
●● A pond lacks emergency spillway. What risk exists?
Answer: Overtopping failure
,●● An infiltration BMP is placed in high groundwater. What happens?
Answer: It fails or is noncompliant
●● A system has low velocities. What issue occurs?
Answer: Sediment buildup
●● A system has excessive velocity. What issue occurs?
Answer: Erosion
●● A design matches peak flow but ignores volume. What is missing?
Answer: Water quality compliance
●● What conditions make a project "redevelopment" under Section 3.5?
Answer: It is development on a previously developed site where
impervious surface exceeds 20 percent of the total site and
improvements to the subject property exceed 50 percent of the total site
value.
●● What activities are expressly included within "redevelopment" for
Section 3.5 purposes?
Answer: Remodeling of existing building interiors, resurfacing of paved
areas, and exterior building changes are included.
,●● What activities are expressly excluded from "redevelopment"?
Answer: Ordinary maintenance activities that do not increase or
concentrate stormwater runoff or cause additional nonpoint source
pollution are excluded.
●● To what area do Section 3.5 redevelopment requirements apply?
Answer: They apply to the entire parcel in question, but do not apply to
parcel areas less than 1 acre or sites with a greater than 80 percent
existing building footprint that is not being removed.
●● What are the three alternative redevelopment performance standards
in Section 3.5.1?
Answer: (1) Reduce impervious cover on the site by at least 20 percent;
or (2) achieve a 10 percent reduction in the 24-hour runoff volume from
the 50 percent AEP storm while confirming post-development peak
discharge does not exceed pre-development for that storm; or (3) reduce
post-development peak discharge rates by 10 percent of existing peak
discharge rates for the 10 percent and 4 percent AEP storms while
confirming the 24-hour post-development volume does not exceed pre-
development volume for those storms.
●● What special note applies if permeable pavers are used only to
satisfy the 20 percent impervious cover reduction option?
, Answer: If they meet the material and construction requirements of the
LID guide, they do not require infiltration or Seasonal High Water Table
testing.
●● For non-special protection areas, when may the redevelopment
performance standards in Section 3.5.1 be bypassed?
Answer: Only if adequate downstream storm drainage conveyance
capacity all the way to receiving waters can be demonstrated.
●● For special protection areas, how do redevelopment standards
interact with other requirements?
Answer: One of the redevelopment requirements must still be applied, in
addition to the requirements in Sections 3.9.3 and 3.6.
●● What are the two redevelopment exemptions listed in Section 3.5.2?
Answer: (1) Construction or improvement of an SFR, except for SFR in
a special protection area adding 500 square feet or more of impervious
area; and (2) minor land-disturbing activities that do not disturb more
than 0.5 acres, are not part of an LCP, are not in a special protection
area, and do not increase post-development impervious area by greater
than 10 percent of the impervious area at the time of CAA submittal.
●● What approval condition applies to redevelopment exemptions?
Answer: They must be documented for City approval as stated in
Section 4.10.
