AUSTIN (KXAN) — On Wednesday, Austin’s new Land Development Code (LDC) inched closer to becoming reality.

The 1,366-page overhaul of the city’s land use rules, along with amendments, passed the first reading with a 7-4 vote. Council members, Kathie Tovo, Ann Kitchen, Alison Alter and Leslie Pool, voted against the proposal.

The LDC dictates what kind of buildings can be built in different parts of the city. It’s designed to add hundreds of thousands of new homes and increase affordability.

The draft code will need two more rounds of approvals. The final vote is expected by late March.

Throughout the revision process, however, many people asked, “If we’re adding density, is that going to make flooding even worse?”

At LDC pubic hearings, dozens of people voiced their concerns.

Flood mitigation features in the code

Anna Farrell-Sherman, Clean Water Associate at Environment Texas, said she fully understands the risk of flooding in Austin.

“My street, whenever it rains heavily, there’s a river of water running down the side of the street,” she said.

Farrell-Sherman believes the new code, if approved two more times to go into effect, will be a welcome change because more buildings will be required to have flood mitigation features.

She explained, “The first is that it mandates use of nature-based infrastructure, which is rain gardens, green rooms, anything that lets water soak in.”

An example of a rain garden. (Photo Courtesy: Anna Farrell-Sherman)

An example Farrell-Sherman gave is a rain garden.

Rain gardens are depressed landscape features. They fill up when it rains. The water then slowly drains, instead of flooding nearby roads.

City officials explained to KXAN the term they use is “green stormwater infrastructure” or GSI. “On commercial, multifamily, industrial, and civic (e.g., schools) projects and new residential subdivisions, GSI is required to slow, filter, and infiltrate stormwater to protect water quality in our creeks, lakes, and other water bodies  and provide other environmental benefits,” they said.

Single-family construction and “missing middle” housing would be exempt.

Farrell-Sherman said the code also ends certain exceptions for builders redeveloping an existing building. An example she gave is a car dealership.

“A big parking lot at a car dealership that already has a lot of concrete on it. [Right now] a developer can build a new building that takes up exactly the same amount of concrete without doing anything to help prevent flooding, she said. “Under the new code, they’ll have to reduce the amount of ground that’s covered and add water quality controls, flood controls to help prevent flooding and water pollution.”

Atlas 14 and Land Development Code

We also sat down with Felicia Foster, principal at Barron Custom Design.

She said density isn’t the cause of flooding. “Most of the flooding that’s currently occurring are older areas that have not been following our current drainage standards in our drainage criteria manual, environmental criteria manual, building criteria manual,” she said.

The code aims to add density in “transition areas” and “high opportunity areas.”

Foster said, “The additional density where we’re putting it, along the corridors, those areas are built to handle it.”

However, even if a street is upzoned, Foster told KXAN, “Flood zone’s going to trump the new Land Development Code.”

Last month, City Council voted to expand Austin’s 100-year floodplain. That means the city’s following the new rainfall map called Atlas 14, adding more than 3,000 homes and businesses to flood zones.

If your lot is upzoned to allow up to three units under the new LDC, but it’s located in a flood zone, Foster said you’ll still be limited to just one unit.

“Flood map, because it is a life safety issue, that is going to take precedent over any entitlements the new LDC may open up,” she explained.

City officials said:

“The new land development code will include the recently council-approved Atlas 14 floodplain ordinance. This ordinance was not yet ready for inclusion in the first draft that the council passed on first reading, but it will be included in the next draft in its entirety. The new larger floodplains from Atlas 14 were used to inform the mapping of the new zoning categories. For example, no new ”missing middle” residential zones were placed in the floodplains to prevent the expectation of new, additional units in flood hazard areas.