Do we have enough subsidence monitors?
Lone Star board members say we don't have enough subsidence monitoring stations in Montgomery County. They say our monitoring is "sparse", but the spacing is comparable to other Districts in the groundwater management area that are adopting the same groundwater rules.
The map here shows Port-A-Measure or PAM stations with the call sign starting with a P, the other 4-character subsidence measuring stations are CORS sites - Continuously Operating Reference Stations managed by the National Geodetic Survey.
As you can see from the two charts below, we have comparable coverage to other Districts and Counties to detect and monitor sinking with enough accuracy to adjust groundwater pumping.
While more monitors would be useful to validate the subsidence model and protect areas that are not covered, the lack of those monitors shouldn’t prevent us from adopting groundwater rules that protect us from sinking.
Subsidence monitor distribution by District. Bluebonnet, SE Texas and Lower Trinity cover multiple counties. For example, Bluebonnet Groundwater Conservation District includes Austin, Waller, Grimes and Walker County.
Subsidence monitor distribution by county (some districts include multiple counties, Lone Star only covers Montgomery County).
Even on a per-county basis, Lone Star Groundwater Conservation District is in the top quarter when it comes to number of subsidence monitoring stations, and they all show that we're sinking from aggressive groundwater pumping.
WHY THIS MATTERS: Our homes, roads and businesses are structurally supported by the water underground, so if we use too much groundwater we cause our land to sink. Parts of Montgomery County have sunk one foot in the past 20 years, and some areas are expected to sink 3 MORE feet by 2080. This sinking is irreversible and causes damage to our homes, roads and businesses from flooding and fault activation.
OUR RECOMMENDATION: Rather than increasing groundwater use and risk irreversible and negligent subsidence, we should limit groundwater use to prevent subsidence, and ramp up use of surface water to meet growing demand.
TAKE ACTION: Please let LSGCD know what you think by email to info@lonestargcd.org with the subject line “DFC Comments” no later than 11:59 p.m. on Jul. 19, 2021.
