What is the Drainage Criteria Manual?
The Drainage Criteria Manual is a set of engineering design policies and standards for managing stormwater and drainage in Lakewood. It is a technical document that includes calculations for projecting stormwater flows, standards for designing drainage infrastructure such as detention ponds and underground stormwater pipes, and specification for things such as gutters and outlet structures. The manual is adopted by City Council as part of the Lakewood Municipal Code and is a mandatory document to stay in compliance with state and federal regulations for water quality.
Who uses the drainage manual?
Engineers, developers, city staff, and partner agencies like the Mile High Flood District uses the manual to design and construct drainage systems in compliance with adopted engineering standards and state regulatory requirements. It is also used to review proposed land development plans and stormwater infrastructure designs to ensure that the proposed drainage systems meet city standards.
Why does the manual need to be updated?
The criteria in the manual need to be updated because the existing manual was last substantially revised in 1982, and stormwater engineering practices have advanced significantly since that address stormwater as a vital resource in urban ecosystems. Best practices for hydrology, water quality treatment, and flood control design have changed, and the current manual lacks many of the detailed standards and policies needed to address today’s development patterns and regulatory obligations.
How does the drainage criteria update affect me?
Most residents will not be directly affected by the update because it is primarily a technical engineering document used for land development and infrastructure projects. However, the overall community will benefit by ensuring that new development is designed to reduce flooding risks to neighborhoods, streets, parks, and community assets, making Lakewood safer and more resilient during severe storms.
Updated criteria also help improve local water quality by requiring better filtration, detention, and pollution‑control measures that protect streams and lakes used for recreation and habitat. Additionally, residents benefit from an improved and well‑maintained stormwater system funded through the existing stormwater management utility, which helps prevent drainage failures and reduces emergency repair needs.
Will the updates address climate change?
Yes, the new criteria will address changing climate conditions by incorporating updated design practices and stormwater modeling that reflect the increasing intensity and frequency of rainfall events.
Will the new criteria Include the use of green infrastructure and nature-based solutions?
Yes, the new criteria will include green and natural designs by requiring or encouraging low-impact development strategies such as on‑site stormwater filtration, permeable pavement, and naturally landscaped detention areas.
What will this cost?
The direct cost of updating the manual will be shared equally between the city and the Mile High Flood District. Developers of new residential and commercial projects may face cost impacts due to potential changes in criteria. Cost estimate comparisons between the old and new standards will be shared as the project progresses.
However, without updating the manual, the city could face higher long‑term costs due to the need for more infrastructure and maintenance, increased flooding, and additional emergency repair expenses. Those costs would ultimately be reflected in future funding needs.
What is the Drainage Criteria Manual?
The Drainage Criteria Manual is a set of engineering design policies and standards for managing stormwater and drainage in Lakewood. It is a technical document that includes calculations for projecting stormwater flows, standards for designing drainage infrastructure such as detention ponds and underground stormwater pipes, and specification for things such as gutters and outlet structures. The manual is adopted by City Council as part of the Lakewood Municipal Code and is a mandatory document to stay in compliance with state and federal regulations for water quality.
Who uses the drainage manual?
Engineers, developers, city staff, and partner agencies like the Mile High Flood District uses the manual to design and construct drainage systems in compliance with adopted engineering standards and state regulatory requirements. It is also used to review proposed land development plans and stormwater infrastructure designs to ensure that the proposed drainage systems meet city standards.
Why does the manual need to be updated?
The criteria in the manual need to be updated because the existing manual was last substantially revised in 1982, and stormwater engineering practices have advanced significantly since that address stormwater as a vital resource in urban ecosystems. Best practices for hydrology, water quality treatment, and flood control design have changed, and the current manual lacks many of the detailed standards and policies needed to address today’s development patterns and regulatory obligations.
How does the drainage criteria update affect me?
Most residents will not be directly affected by the update because it is primarily a technical engineering document used for land development and infrastructure projects. However, the overall community will benefit by ensuring that new development is designed to reduce flooding risks to neighborhoods, streets, parks, and community assets, making Lakewood safer and more resilient during severe storms.
Updated criteria also help improve local water quality by requiring better filtration, detention, and pollution‑control measures that protect streams and lakes used for recreation and habitat. Additionally, residents benefit from an improved and well‑maintained stormwater system funded through the existing stormwater management utility, which helps prevent drainage failures and reduces emergency repair needs.
Will the updates address climate change?
Yes, the new criteria will address changing climate conditions by incorporating updated design practices and stormwater modeling that reflect the increasing intensity and frequency of rainfall events.
Will the new criteria Include the use of green infrastructure and nature-based solutions?
Yes, the new criteria will include green and natural designs by requiring or encouraging low-impact development strategies such as on‑site stormwater filtration, permeable pavement, and naturally landscaped detention areas.
What will this cost?
The direct cost of updating the manual will be shared equally between the city and the Mile High Flood District. Developers of new residential and commercial projects may face cost impacts due to potential changes in criteria. Cost estimate comparisons between the old and new standards will be shared as the project progresses.
However, without updating the manual, the city could face higher long‑term costs due to the need for more infrastructure and maintenance, increased flooding, and additional emergency repair expenses. Those costs would ultimately be reflected in future funding needs.
