More Aquifer Discussion

Dear Editor,
    Douglas Watkins states [“Postmarks Online,” Jan. 24], “My letter does not state that all recharge from Williamson Creek discharges to Cold Springs.” However, his Jan. 20 [“Postmarks”] letter states, “runoff and groundwater from the Lantana track (and the contributing zone north of Highway 71) would drain to the hydrologically distinct Cold Springs Basin segment of the Edwards Aquifer system and thence flow northeastward to emerge at Cold Springs on Town Lake, thereby passing Barton Springs entirely.”
    As I stated earlier this is not true because:
    1) the Lantana track is in the Williamson Creek basin contributing zone;
    2) runoff from this contributing zone is upstream from, thus feeds the entire recharge zone on Williamson Creek; and
    3) dye studies (and other data referenced earlier by me) show that some if not most of the recharge from Williamson Creek discharges to Barton Springs.
    Additionally, Mr. Watkins feels that 3.3% impervious cover is “extensive” development, but all such measures I know indicate such values to represent very or extremely rural areas.
    Mr. Watkins also fails to realize that future impervious cover values outside Austin's jurisdiction could exceed those (14.9%) predicted to be within the city's jurisdiction (www.cityofaustin.org/watershed/downloads/bart_inv4.2_.pdf). Such is possible because Austin's ordinances (those limiting impervious cover) don't apply to areas outside the city – most of that area has no impervious cover limits.
    Each letter written by Mr. Watkins contains several false statements, perhaps because he is a petroleum exploration geologist rather than a water geologist and perhaps he hasn't studied the Edwards Aquifer. As I mentioned in my Jan. 27 letter [“Postmarks”], organic carbon at Barton Springs has increased 180% even with little development. Based on this, perhaps Mr. Watkins wants the aquifer to be fully developed so that he can explore for petroleum in the Edwards Aquifer.